| Message ID | 20220222152758.207415-1-kshitij.suri@nutanix.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Added parameter to take screenshot with screendump as PNG | expand |
On Tue, Feb 22, 2022 at 03:27:58PM +0000, Kshitij Suri wrote: > Currently screendump only supports PPM format, which is un-compressed and not > standard. Added an "format" parameter to qemu monitor screendump capabilites > to support PNG image capture using libpng. The param was added in QAPI schema > of screendump present in ui.json along with png_save() function which converts > pixman_image to PNG. HMP command equivalent was also modified to support the > feature. > > Example usage: > { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/718 > > Signed-off-by: Kshitij Suri <kshitij.suri@nutanix.com> > --- > hmp-commands.hx | 11 ++-- > monitor/hmp-cmds.c | 4 +- > qapi/ui.json | 7 ++- > ui/console.c | 153 ++++++++++++++++++++++++++++++++++++++++++++- > 4 files changed, 165 insertions(+), 10 deletions(-) You're going to need to update configure here. Currently libpng is only detected if VNC is enabled. This proposed change means we need to detect libpng any time the build of system emulators is enabled. The CONFIG_VNC_PNG option will also need renaming to CONFIG_PNG > + .args_type = "filename:F,device:s?,head:i?,format:f?", > + .params = "filename [device [head]] [format]", > + .help = "save screen from head 'head' of display device 'device'" > + "in specified format 'format' as image 'filename'." > + "Default format for screendump is PPM.", Mention what other formats are permitted, making it clear that the format is in fact 'png' and 'ppm', not 'PPM' > diff --git a/qapi/ui.json b/qapi/ui.json > index 9354f4c467..9fdb56b60b 100644 > --- a/qapi/ui.json > +++ b/qapi/ui.json > @@ -76,7 +76,7 @@ > ## > # @screendump: > # > -# Write a PPM of the VGA screen to a file. > +# Write a screenshot of the VGA screen to a file. > # > # @filename: the path of a new PPM file to store the image > # > @@ -87,6 +87,9 @@ > # parameter is missing, head #0 will be used. Also note that the head > # can only be specified in conjunction with the device ID. (Since 2.12) > # > +# @format: image format for screendump is specified. Currently only PNG and > +# PPM are supported. > +# > # Returns: Nothing on success > # > # Since: 0.14 > @@ -99,7 +102,7 @@ > # > ## > { 'command': 'screendump', > - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, > + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', '*format': 'str'}, This 'format' should not be a string, it needs to be an enum type. > 'coroutine': true } > > ## > diff --git a/ui/console.c b/ui/console.c > index 40eebb6d2c..7813b195ac 100644 > --- a/ui/console.c > +++ b/ui/console.c > @@ -37,6 +37,9 @@ > #include "exec/memory.h" > #include "io/channel-file.h" > #include "qom/object.h" > +#ifdef CONFIG_VNC_PNG > +#include "png.h" > +#endif > > #define DEFAULT_BACKSCROLL 512 > #define CONSOLE_CURSOR_PERIOD 500 > @@ -289,6 +292,137 @@ void graphic_hw_invalidate(QemuConsole *con) > } > } > > +#ifdef CONFIG_VNC_PNG > +/** > + * a8r8g8b8_to_rgba: Convert a8r8g8b8 to rgba format > + * > + * @dst: Destination pointer. > + * @src: Source pointer. > + * @n_pixels: Size of image. > + */ > +static void a8r8g8b8_to_rgba(uint32_t *dst, uint32_t *src, int n_pixels) > +{ > + uint8_t *dst8 = (uint8_t *)dst; > + int i; > + > + for (i = 0; i < n_pixels; ++i) { > + uint32_t p = src[i]; > + uint8_t a, r, g, b; > + > + a = (p & 0xff000000) >> 24; > + r = (p & 0x00ff0000) >> 16; > + g = (p & 0x0000ff00) >> 8; > + b = (p & 0x000000ff) >> 0; > + > + if (a != 0) { > + #define DIVIDE(c, a) \ > + do { \ > + int t = ((c) * 255) / a; \ > + (c) = t < 0 ? 0 : t > 255 ? 255 : t; \ > + } while (0) > + > + DIVIDE(r, a); > + DIVIDE(g, a); > + DIVIDE(b, a); > + #undef DIVIDE > + } > + > + *dst8++ = r; > + *dst8++ = g; > + *dst8++ = b; > + *dst8++ = a; > + } > +} > + > +/** > + * png_save: Take a screenshot as PNG > + * > + * Saves screendump as a PNG file > + * > + * Returns true for success or false for error. > + * Inspired from png test utils from https://github.com/aseprite/pixman > + * > + * @fd: File descriptor for PNG file. > + * @image: Image data in pixman format. > + * @errp: Pointer to an error. > + */ > +static bool png_save(int fd, pixman_image_t *image, Error **errp) > +{ > + int width = pixman_image_get_width(image); > + int height = pixman_image_get_height(image); > + int stride = width * 4; > + g_autofree uint32_t *src_data = g_malloc(height * stride); > + g_autofree uint32_t *dest_data = g_malloc(height * stride); > + g_autoptr(pixman_image_t) src_copy; > + g_autoptr(pixman_image_t) dest_copy; > + g_autofree png_struct *write_struct; > + g_autofree png_info *info_struct; Anything declared with 'g_auto*' must always be explicitly initialized to NULL at time of declaration to avoid risk of gree'ing uninitialized memory > + g_autofree png_bytep *row_pointers = g_malloc(height * sizeof(png_bytep)); g_new(png_bytep, height) > + FILE *f = fdopen(fd, "wb"); > + int y; > + if (!f) { > + error_setg(errp, "Failed to create file from file descriptor"); > + return false; > + } > + > + src_copy = pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height, > + src_data, stride); > + > + pixman_image_composite32(PIXMAN_OP_SRC, image, NULL, src_copy, 0, 0, 0, 0, > + 0, 0, width, height); > + > + memcpy(dest_data, src_data, sizeof(*src_data)); > + > + a8r8g8b8_to_rgba(dest_data, src_data, height * width); > + > + for (y = 0; y < height; ++y) { > + row_pointers[y] = (png_bytep)(src_data + y * width); > + } > + > + write_struct = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, > + NULL, NULL); > + if (!write_struct) { > + error_setg(errp, "PNG creation failed. Unable to write struct"); > + return false; > + } > + > + info_struct = png_create_info_struct(write_struct); > + > + if (!info_struct) { > + error_setg(errp, "PNG creation failed. Unable to write info"); > + return false; > + } > + > + png_init_io(write_struct, f); > + > + png_set_IHDR(write_struct, info_struct, width, height, 8, > + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, > + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); > + > + png_write_info(write_struct, info_struct); > + > + png_write_image(write_struct, row_pointers); > + > + png_write_end(write_struct, NULL); > + > + if (fclose(f) != 0) { > + error_setg(errp, "PNG creation failed. Unable to close file"); > + return false; > + } > + > + return true; > +} > + > +#else /* no png support */ > + > +static bool png_save(int fd, pixman_image_t *image, Error **errp) > +{ > + error_setg(errp, "Enable VNC PNG support for png screendump"); > + return false; > +} > + > +#endif /* CONFIG_VNC_PNG */ > + > static bool ppm_save(int fd, pixman_image_t *image, Error **errp) > { > int width = pixman_image_get_width(image); > @@ -327,7 +461,8 @@ static void graphic_hw_update_bh(void *con) > /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ > void coroutine_fn > qmp_screendump(const char *filename, bool has_device, const char *device, > - bool has_head, int64_t head, Error **errp) > + bool has_head, int64_t head, bool has_format, > + const char *format, Error **errp) > { > g_autoptr(pixman_image_t) image = NULL; > QemuConsole *con; > @@ -383,8 +518,22 @@ qmp_screendump(const char *filename, bool has_device, const char *device, > * yields and releases the BQL. It could produce corrupted dump, but > * it should be otherwise safe. > */ > - if (!ppm_save(fd, image, errp)) { > + > + if (has_format && strcmp(format, "png") == 0) { > + /* PNG format specified for screendump */ > + if (!png_save(fd, image, errp)) { > + qemu_unlink(filename); > + } > + } else if (!has_format || (has_format && strcmp(format, "ppm") == 0)) { > + /* PPM format specified/default for screendump */ > + if (!ppm_save(fd, image, errp)) { > + qemu_unlink(filename); > + } > + } else { > + /* Invalid specified for screendump */ > + error_setg(errp, "Invalid format provided for screendump."); > qemu_unlink(filename); > + return; > } > } > > -- > 2.22.3 > > Regards, Daniel
* Kshitij Suri (kshitij.suri@nutanix.com) wrote: > Currently screendump only supports PPM format, which is un-compressed and not > standard. Added an "format" parameter to qemu monitor screendump capabilites > to support PNG image capture using libpng. The param was added in QAPI schema > of screendump present in ui.json along with png_save() function which converts > pixman_image to PNG. HMP command equivalent was also modified to support the > feature. > > Example usage: > { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/718 > > Signed-off-by: Kshitij Suri <kshitij.suri@nutanix.com> > --- > hmp-commands.hx | 11 ++-- > monitor/hmp-cmds.c | 4 +- > qapi/ui.json | 7 ++- > ui/console.c | 153 ++++++++++++++++++++++++++++++++++++++++++++- > 4 files changed, 165 insertions(+), 10 deletions(-) > > diff --git a/hmp-commands.hx b/hmp-commands.hx > index 70a9136ac2..2163337f35 100644 > --- a/hmp-commands.hx > +++ b/hmp-commands.hx > @@ -244,17 +244,18 @@ ERST > > { > .name = "screendump", > - .args_type = "filename:F,device:s?,head:i?", > - .params = "filename [device [head]]", > - .help = "save screen from head 'head' of display device 'device' " > - "into PPM image 'filename'", > + .args_type = "filename:F,device:s?,head:i?,format:f?", > + .params = "filename [device [head]] [format]", > + .help = "save screen from head 'head' of display device 'device'" > + "in specified format 'format' as image 'filename'." > + "Default format for screendump is PPM.", > .cmd = hmp_screendump, > .coroutine = true, > }, > > SRST > ``screendump`` *filename* > - Save screen into PPM image *filename*. > + Save screen as image *filename*. > ERST > > { > diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c > index 2669156b28..3fb1394561 100644 > --- a/monitor/hmp-cmds.c > +++ b/monitor/hmp-cmds.c > @@ -1665,9 +1665,11 @@ hmp_screendump(Monitor *mon, const QDict *qdict) > const char *filename = qdict_get_str(qdict, "filename"); > const char *id = qdict_get_try_str(qdict, "device"); > int64_t head = qdict_get_try_int(qdict, "head", 0); > + const char *format = qdict_get_str(qdict, "format"); > Error *err = NULL; > > - qmp_screendump(filename, id != NULL, id, id != NULL, head, &err); > + qmp_screendump(filename, id != NULL, id, id != NULL, head, > + format != NULL, format, &err); > hmp_handle_error(mon, err); > } I think that's OK from the HMP front, see some questions below. > diff --git a/qapi/ui.json b/qapi/ui.json > index 9354f4c467..9fdb56b60b 100644 > --- a/qapi/ui.json > +++ b/qapi/ui.json > @@ -76,7 +76,7 @@ > ## > # @screendump: > # > -# Write a PPM of the VGA screen to a file. > +# Write a screenshot of the VGA screen to a file. > # > # @filename: the path of a new PPM file to store the image > # > @@ -87,6 +87,9 @@ > # parameter is missing, head #0 will be used. Also note that the head > # can only be specified in conjunction with the device ID. (Since 2.12) > # > +# @format: image format for screendump is specified. Currently only PNG and > +# PPM are supported. > +# > # Returns: Nothing on success > # > # Since: 0.14 > @@ -99,7 +102,7 @@ > # > ## > { 'command': 'screendump', > - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, > + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', '*format': 'str'}, > 'coroutine': true } > > ## > diff --git a/ui/console.c b/ui/console.c > index 40eebb6d2c..7813b195ac 100644 > --- a/ui/console.c > +++ b/ui/console.c > @@ -37,6 +37,9 @@ > #include "exec/memory.h" > #include "io/channel-file.h" > #include "qom/object.h" > +#ifdef CONFIG_VNC_PNG > +#include "png.h" > +#endif > > #define DEFAULT_BACKSCROLL 512 > #define CONSOLE_CURSOR_PERIOD 500 > @@ -289,6 +292,137 @@ void graphic_hw_invalidate(QemuConsole *con) > } > } > > +#ifdef CONFIG_VNC_PNG > +/** > + * a8r8g8b8_to_rgba: Convert a8r8g8b8 to rgba format > + * > + * @dst: Destination pointer. > + * @src: Source pointer. > + * @n_pixels: Size of image. > + */ > +static void a8r8g8b8_to_rgba(uint32_t *dst, uint32_t *src, int n_pixels) > +{ > + uint8_t *dst8 = (uint8_t *)dst; > + int i; > + > + for (i = 0; i < n_pixels; ++i) { > + uint32_t p = src[i]; > + uint8_t a, r, g, b; > + > + a = (p & 0xff000000) >> 24; > + r = (p & 0x00ff0000) >> 16; > + g = (p & 0x0000ff00) >> 8; > + b = (p & 0x000000ff) >> 0; > + > + if (a != 0) { > + #define DIVIDE(c, a) \ > + do { \ > + int t = ((c) * 255) / a; \ > + (c) = t < 0 ? 0 : t > 255 ? 255 : t; \ I can't see how 't' can be less than 0 here? > + } while (0) > + > + DIVIDE(r, a); > + DIVIDE(g, a); > + DIVIDE(b, a); > + #undef DIVIDE > + } > + > + *dst8++ = r; > + *dst8++ = g; > + *dst8++ = b; > + *dst8++ = a; > + } > +} Now, I'm not too much of a graphics person, but I'm a bit confused; this seems to be applying the alpha scaling to the r/g/b/ data - but then still including the alpha value in the output; doesn't that mean that the thing displaying the result will also apply the alpha scaling again? > +/** > + * png_save: Take a screenshot as PNG > + * > + * Saves screendump as a PNG file > + * > + * Returns true for success or false for error. > + * Inspired from png test utils from https://github.com/aseprite/pixman > + * > + * @fd: File descriptor for PNG file. > + * @image: Image data in pixman format. > + * @errp: Pointer to an error. > + */ > +static bool png_save(int fd, pixman_image_t *image, Error **errp) > +{ > + int width = pixman_image_get_width(image); > + int height = pixman_image_get_height(image); > + int stride = width * 4; > + g_autofree uint32_t *src_data = g_malloc(height * stride); > + g_autofree uint32_t *dest_data = g_malloc(height * stride); > + g_autoptr(pixman_image_t) src_copy; > + g_autoptr(pixman_image_t) dest_copy; > + g_autofree png_struct *write_struct; > + g_autofree png_info *info_struct; > + g_autofree png_bytep *row_pointers = g_malloc(height * sizeof(png_bytep)); > + FILE *f = fdopen(fd, "wb"); > + int y; > + if (!f) { > + error_setg(errp, "Failed to create file from file descriptor"); > + return false; > + } > + > + src_copy = pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height, > + src_data, stride); > + > + pixman_image_composite32(PIXMAN_OP_SRC, image, NULL, src_copy, 0, 0, 0, 0, > + 0, 0, width, height); Nothing in the rest of qemu uses pixman_image_composite*32* - all the rest uses the plain version; what's the difference? > + memcpy(dest_data, src_data, sizeof(*src_data)); Why if you're just about to nuke dest_data with the converted version? > + a8r8g8b8_to_rgba(dest_data, src_data, height * width); > + > + for (y = 0; y < height; ++y) { > + row_pointers[y] = (png_bytep)(src_data + y * width); > + } > + > + write_struct = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, > + NULL, NULL); > + if (!write_struct) { > + error_setg(errp, "PNG creation failed. Unable to write struct"); > + return false; > + } > + > + info_struct = png_create_info_struct(write_struct); > + > + if (!info_struct) { > + error_setg(errp, "PNG creation failed. Unable to write info"); > + return false; > + } > + > + png_init_io(write_struct, f); > + > + png_set_IHDR(write_struct, info_struct, width, height, 8, > + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, > + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); > + > + png_write_info(write_struct, info_struct); > + > + png_write_image(write_struct, row_pointers); Had you considered using png_write_row and avoiding having to hold/allocate the destination and row_pointers at all? (In actual fact, can you steal the code in ui/vnc-enc-tight.c send_png_rect ? ) Dave > + png_write_end(write_struct, NULL); > + > + if (fclose(f) != 0) { > + error_setg(errp, "PNG creation failed. Unable to close file"); > + return false; > + } > + > + return true; > +} > + > +#else /* no png support */ > + > +static bool png_save(int fd, pixman_image_t *image, Error **errp) > +{ > + error_setg(errp, "Enable VNC PNG support for png screendump"); > + return false; > +} > + > +#endif /* CONFIG_VNC_PNG */ > + > static bool ppm_save(int fd, pixman_image_t *image, Error **errp) > { > int width = pixman_image_get_width(image); > @@ -327,7 +461,8 @@ static void graphic_hw_update_bh(void *con) > /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ > void coroutine_fn > qmp_screendump(const char *filename, bool has_device, const char *device, > - bool has_head, int64_t head, Error **errp) > + bool has_head, int64_t head, bool has_format, > + const char *format, Error **errp) > { > g_autoptr(pixman_image_t) image = NULL; > QemuConsole *con; > @@ -383,8 +518,22 @@ qmp_screendump(const char *filename, bool has_device, const char *device, > * yields and releases the BQL. It could produce corrupted dump, but > * it should be otherwise safe. > */ > - if (!ppm_save(fd, image, errp)) { > + > + if (has_format && strcmp(format, "png") == 0) { > + /* PNG format specified for screendump */ > + if (!png_save(fd, image, errp)) { > + qemu_unlink(filename); > + } > + } else if (!has_format || (has_format && strcmp(format, "ppm") == 0)) { > + /* PPM format specified/default for screendump */ > + if (!ppm_save(fd, image, errp)) { > + qemu_unlink(filename); > + } > + } else { > + /* Invalid specified for screendump */ > + error_setg(errp, "Invalid format provided for screendump."); > qemu_unlink(filename); > + return; > } > } > > -- > 2.22.3 >
On Tue, Feb 22, 2022 at 03:27:58PM +0000, Kshitij Suri wrote: > Currently screendump only supports PPM format, which is un-compressed and not > standard. Added an "format" parameter to qemu monitor screendump capabilites > to support PNG image capture using libpng. The param was added in QAPI schema > of screendump present in ui.json along with png_save() function which converts > pixman_image to PNG. HMP command equivalent was also modified to support the > feature. > > Example usage: > { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } > > Resolves: https://gitlab.com/qemu-project/qemu/-/issues/718 > > Signed-off-by: Kshitij Suri <kshitij.suri@nutanix.com> > --- > hmp-commands.hx | 11 ++-- > monitor/hmp-cmds.c | 4 +- > qapi/ui.json | 7 ++- > ui/console.c | 153 ++++++++++++++++++++++++++++++++++++++++++++- > 4 files changed, 165 insertions(+), 10 deletions(-) > > diff --git a/hmp-commands.hx b/hmp-commands.hx > index 70a9136ac2..2163337f35 100644 > --- a/hmp-commands.hx > +++ b/hmp-commands.hx > @@ -244,17 +244,18 @@ ERST > > { > .name = "screendump", > - .args_type = "filename:F,device:s?,head:i?", > - .params = "filename [device [head]]", > - .help = "save screen from head 'head' of display device 'device' " > - "into PPM image 'filename'", > + .args_type = "filename:F,device:s?,head:i?,format:f?", > + .params = "filename [device [head]] [format]", > + .help = "save screen from head 'head' of display device 'device'" > + "in specified format 'format' as image 'filename'." > + "Default format for screendump is PPM.", > .cmd = hmp_screendump, > .coroutine = true, > }, > > SRST > ``screendump`` *filename* > - Save screen into PPM image *filename*. > + Save screen as image *filename*. > ERST > > { > diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c > index 2669156b28..3fb1394561 100644 > --- a/monitor/hmp-cmds.c > +++ b/monitor/hmp-cmds.c > @@ -1665,9 +1665,11 @@ hmp_screendump(Monitor *mon, const QDict *qdict) > const char *filename = qdict_get_str(qdict, "filename"); > const char *id = qdict_get_try_str(qdict, "device"); > int64_t head = qdict_get_try_int(qdict, "head", 0); > + const char *format = qdict_get_str(qdict, "format"); > Error *err = NULL; > > - qmp_screendump(filename, id != NULL, id, id != NULL, head, &err); > + qmp_screendump(filename, id != NULL, id, id != NULL, head, > + format != NULL, format, &err); > hmp_handle_error(mon, err); > } > > diff --git a/qapi/ui.json b/qapi/ui.json > index 9354f4c467..9fdb56b60b 100644 > --- a/qapi/ui.json > +++ b/qapi/ui.json > @@ -76,7 +76,7 @@ > ## > # @screendump: > # > -# Write a PPM of the VGA screen to a file. > +# Write a screenshot of the VGA screen to a file. > # > # @filename: the path of a new PPM file to store the image > # > @@ -87,6 +87,9 @@ > # parameter is missing, head #0 will be used. Also note that the head > # can only be specified in conjunction with the device ID. (Since 2.12) > # > +# @format: image format for screendump is specified. Currently only PNG and > +# PPM are supported. > +# > # Returns: Nothing on success > # > # Since: 0.14 > @@ -99,7 +102,7 @@ > # > ## > { 'command': 'screendump', > - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, > + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', '*format': 'str'}, > 'coroutine': true } > > ## > diff --git a/ui/console.c b/ui/console.c > index 40eebb6d2c..7813b195ac 100644 > --- a/ui/console.c > +++ b/ui/console.c > @@ -37,6 +37,9 @@ > #include "exec/memory.h" > #include "io/channel-file.h" > #include "qom/object.h" > +#ifdef CONFIG_VNC_PNG > +#include "png.h" > +#endif > > #define DEFAULT_BACKSCROLL 512 > #define CONSOLE_CURSOR_PERIOD 500 > @@ -289,6 +292,137 @@ void graphic_hw_invalidate(QemuConsole *con) > } > } > > +#ifdef CONFIG_VNC_PNG > +/** > + * a8r8g8b8_to_rgba: Convert a8r8g8b8 to rgba format > + * > + * @dst: Destination pointer. > + * @src: Source pointer. > + * @n_pixels: Size of image. > + */ > +static void a8r8g8b8_to_rgba(uint32_t *dst, uint32_t *src, int n_pixels) > +{ > + uint8_t *dst8 = (uint8_t *)dst; > + int i; > + > + for (i = 0; i < n_pixels; ++i) { > + uint32_t p = src[i]; > + uint8_t a, r, g, b; > + > + a = (p & 0xff000000) >> 24; > + r = (p & 0x00ff0000) >> 16; > + g = (p & 0x0000ff00) >> 8; > + b = (p & 0x000000ff) >> 0; > + > + if (a != 0) { > + #define DIVIDE(c, a) \ > + do { \ > + int t = ((c) * 255) / a; \ > + (c) = t < 0 ? 0 : t > 255 ? 255 : t; \ > + } while (0) > + > + DIVIDE(r, a); > + DIVIDE(g, a); > + DIVIDE(b, a); > + #undef DIVIDE > + } > + > + *dst8++ = r; > + *dst8++ = g; > + *dst8++ = b; > + *dst8++ = a; > + } > +} > + > +/** > + * png_save: Take a screenshot as PNG > + * > + * Saves screendump as a PNG file > + * > + * Returns true for success or false for error. > + * Inspired from png test utils from https://github.com/aseprite/pixman > + * > + * @fd: File descriptor for PNG file. > + * @image: Image data in pixman format. > + * @errp: Pointer to an error. > + */ > +static bool png_save(int fd, pixman_image_t *image, Error **errp) > +{ > + int width = pixman_image_get_width(image); > + int height = pixman_image_get_height(image); > + int stride = width * 4; > + g_autofree uint32_t *src_data = g_malloc(height * stride); > + g_autofree uint32_t *dest_data = g_malloc(height * stride); > + g_autoptr(pixman_image_t) src_copy; > + g_autoptr(pixman_image_t) dest_copy; > + g_autofree png_struct *write_struct; > + g_autofree png_info *info_struct; > + g_autofree png_bytep *row_pointers = g_malloc(height * sizeof(png_bytep)); > + FILE *f = fdopen(fd, "wb"); > + int y; > + if (!f) { > + error_setg(errp, "Failed to create file from file descriptor"); > + return false; > + } > + > + src_copy = pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height, > + src_data, stride); > + > + pixman_image_composite32(PIXMAN_OP_SRC, image, NULL, src_copy, 0, 0, 0, 0, > + 0, 0, width, height); > + > + memcpy(dest_data, src_data, sizeof(*src_data)); > + > + a8r8g8b8_to_rgba(dest_data, src_data, height * width); dest_data is not used after this point... > + > + for (y = 0; y < height; ++y) { > + row_pointers[y] = (png_bytep)(src_data + y * width); Here you are setting things up for libpng to write out 'src_data'. So what was the point in the dest_data allocation & conversion ? > + } > + > + write_struct = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, > + NULL, NULL); > + if (!write_struct) { > + error_setg(errp, "PNG creation failed. Unable to write struct"); > + return false; > + } > + > + info_struct = png_create_info_struct(write_struct); > + > + if (!info_struct) { > + error_setg(errp, "PNG creation failed. Unable to write info"); > + return false; > + } > + > + png_init_io(write_struct, f); > + > + png_set_IHDR(write_struct, info_struct, width, height, 8, > + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, > + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); > + > + png_write_info(write_struct, info_struct); > + > + png_write_image(write_struct, row_pointers); > + > + png_write_end(write_struct, NULL); > + > + if (fclose(f) != 0) { > + error_setg(errp, "PNG creation failed. Unable to close file"); > + return false; > + } > + > + return true; > +} Regards, Daniel
On 22/02/22 10:04 pm, Daniel P. Berrangé wrote: > On Tue, Feb 22, 2022 at 03:27:58PM +0000, Kshitij Suri wrote: >> Currently screendump only supports PPM format, which is un-compressed and not >> standard. Added an "format" parameter to qemu monitor screendump capabilites >> to support PNG image capture using libpng. The param was added in QAPI schema >> of screendump present in ui.json along with png_save() function which converts >> pixman_image to PNG. HMP command equivalent was also modified to support the >> feature. >> >> Example usage: >> { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } >> >> Resolves:https://urldefense.proofpoint.com/v2/url?u=https-3A__gitlab.com_qemu-2Dproject_qemu_-2D_issues_718&d=DwIBaQ&c=s883GpUCOChKOHiocYtGcg&r=utjv19Ej9Fb0TB7_DX0o3faQ-OAm2ypPniPyqVSoj_w&m=eOSxOmlj_wVOfj7HF2fJ1VXlNNJp4k8UAlT5STcoAguScPKeHYwb6hwEuY54ok5c&s=ou3KExLg2-Cx31UtMV6vXErHpesdEHJjHXnbKcE9Wdk&e= >> >> Signed-off-by: Kshitij Suri<kshitij.suri@nutanix.com> >> --- >> hmp-commands.hx | 11 ++-- >> monitor/hmp-cmds.c | 4 +- >> qapi/ui.json | 7 ++- >> ui/console.c | 153 ++++++++++++++++++++++++++++++++++++++++++++- >> 4 files changed, 165 insertions(+), 10 deletions(-) > You're going to need to update configure here. > > Currently libpng is only detected if VNC is enabled. > > This proposed change means we need to detect libpng > any time the build of system emulators is enabled. > > The CONFIG_VNC_PNG option will also need renaming > to CONFIG_PNG Yes I have added a new CONFIG_PNG option in the updated patch. As for CONFIG_VNC_PNG, can we have a seperate patch set where I can replace CONFIG_VNC_PNG usage with combination of CONFIG_VNC and CONFIG_PNG? The replacement strategy would be as follows #ifdef CONFIG_VNC_PNG -> #if defined(CONFIG_VNC) && defined(CONFIG_PNG) Along with this, can we also use the new png meson-option to denote PNG format for VNC as well while maintaining backward compatibility? The change would look like vnc_png = dependency('libpng', required: get_option('vnc_png'), method: 'pkg-config', kwargs: static_kwargs) gets changed to vnc_png = dependency('libpng', required: get_option('vnc_png') || get_option('png'), method: 'pkg-config', kwargs: static_kwargs) > >> + .args_type = "filename:F,device:s?,head:i?,format:f?", >> + .params = "filename [device [head]] [format]", >> + .help = "save screen from head 'head' of display device 'device'" >> + "in specified format 'format' as image 'filename'." >> + "Default format for screendump is PPM.", > Mention what other formats are permitted, making it clear that > the format is in fact 'png' and 'ppm', not 'PPM' Updated in the v2 patch. >> diff --git a/qapi/ui.json b/qapi/ui.json >> index 9354f4c467..9fdb56b60b 100644 >> --- a/qapi/ui.json >> +++ b/qapi/ui.json >> @@ -76,7 +76,7 @@ >> ## >> # @screendump: >> # >> -# Write a PPM of the VGA screen to a file. >> +# Write a screenshot of the VGA screen to a file. >> # >> # @filename: the path of a new PPM file to store the image >> # >> @@ -87,6 +87,9 @@ >> # parameter is missing, head #0 will be used. Also note that the head >> # can only be specified in conjunction with the device ID. (Since 2.12) >> # >> +# @format: image format for screendump is specified. Currently only PNG and >> +# PPM are supported. >> +# >> # Returns: Nothing on success >> # >> # Since: 0.14 >> @@ -99,7 +102,7 @@ >> # >> ## >> { 'command': 'screendump', >> - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, >> + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', '*format': 'str'}, > This 'format' should not be a string, it needs to be an enum type. Modified to an enum with png and ppm types. > >> 'coroutine': true } >> >> ## >> diff --git a/ui/console.c b/ui/console.c >> index 40eebb6d2c..7813b195ac 100644 >> --- a/ui/console.c >> +++ b/ui/console.c >> @@ -37,6 +37,9 @@ >> #include "exec/memory.h" >> #include "io/channel-file.h" >> #include "qom/object.h" >> +#ifdef CONFIG_VNC_PNG >> +#include "png.h" >> +#endif >> >> #define DEFAULT_BACKSCROLL 512 >> #define CONSOLE_CURSOR_PERIOD 500 >> @@ -289,6 +292,137 @@ void graphic_hw_invalidate(QemuConsole *con) >> } >> } >> >> +#ifdef CONFIG_VNC_PNG >> +/** >> + * a8r8g8b8_to_rgba: Convert a8r8g8b8 to rgba format >> + * >> + * @dst: Destination pointer. >> + * @src: Source pointer. >> + * @n_pixels: Size of image. >> + */ >> +static void a8r8g8b8_to_rgba(uint32_t *dst, uint32_t *src, int n_pixels) >> +{ >> + uint8_t *dst8 = (uint8_t *)dst; >> + int i; >> + >> + for (i = 0; i < n_pixels; ++i) { >> + uint32_t p = src[i]; >> + uint8_t a, r, g, b; >> + >> + a = (p & 0xff000000) >> 24; >> + r = (p & 0x00ff0000) >> 16; >> + g = (p & 0x0000ff00) >> 8; >> + b = (p & 0x000000ff) >> 0; >> + >> + if (a != 0) { >> + #define DIVIDE(c, a) \ >> + do { \ >> + int t = ((c) * 255) / a; \ >> + (c) = t < 0 ? 0 : t > 255 ? 255 : t; \ >> + } while (0) >> + >> + DIVIDE(r, a); >> + DIVIDE(g, a); >> + DIVIDE(b, a); >> + #undef DIVIDE >> + } >> + >> + *dst8++ = r; >> + *dst8++ = g; >> + *dst8++ = b; >> + *dst8++ = a; >> + } >> +} >> + >> +/** >> + * png_save: Take a screenshot as PNG >> + * >> + * Saves screendump as a PNG file >> + * >> + * Returns true for success or false for error. >> + * Inspired from png test utils fromhttps://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_aseprite_pixman&d=DwIBaQ&c=s883GpUCOChKOHiocYtGcg&r=utjv19Ej9Fb0TB7_DX0o3faQ-OAm2ypPniPyqVSoj_w&m=eOSxOmlj_wVOfj7HF2fJ1VXlNNJp4k8UAlT5STcoAguScPKeHYwb6hwEuY54ok5c&s=vFM5I_UU7xzQZqH8h-S2oWQgXCcpQbomvm8x9zGso98&e= >> + * >> + * @fd: File descriptor for PNG file. >> + * @image: Image data in pixman format. >> + * @errp: Pointer to an error. >> + */ >> +static bool png_save(int fd, pixman_image_t *image, Error **errp) >> +{ >> + int width = pixman_image_get_width(image); >> + int height = pixman_image_get_height(image); >> + int stride = width * 4; >> + g_autofree uint32_t *src_data = g_malloc(height * stride); >> + g_autofree uint32_t *dest_data = g_malloc(height * stride); >> + g_autoptr(pixman_image_t) src_copy; >> + g_autoptr(pixman_image_t) dest_copy; >> + g_autofree png_struct *write_struct; >> + g_autofree png_info *info_struct; > Anything declared with 'g_auto*' must always be explicitly initialized > to NULL at time of declaration to avoid risk of gree'ing uninitialized > memory Updated the pointers in the updated patch. >> + g_autofree png_bytep *row_pointers = g_malloc(height * sizeof(png_bytep)); > g_new(png_bytep, height) > >> + FILE *f = fdopen(fd, "wb"); >> + int y; >> + if (!f) { >> + error_setg(errp, "Failed to create file from file descriptor"); >> + return false; >> + } >> + >> + src_copy = pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height, >> + src_data, stride); >> + >> + pixman_image_composite32(PIXMAN_OP_SRC, image, NULL, src_copy, 0, 0, 0, 0, >> + 0, 0, width, height); >> + >> + memcpy(dest_data, src_data, sizeof(*src_data)); >> + >> + a8r8g8b8_to_rgba(dest_data, src_data, height * width); >> + >> + for (y = 0; y < height; ++y) { >> + row_pointers[y] = (png_bytep)(src_data + y * width); >> + } >> + >> + write_struct = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, >> + NULL, NULL); >> + if (!write_struct) { >> + error_setg(errp, "PNG creation failed. Unable to write struct"); >> + return false; >> + } >> + >> + info_struct = png_create_info_struct(write_struct); >> + >> + if (!info_struct) { >> + error_setg(errp, "PNG creation failed. Unable to write info"); >> + return false; >> + } >> + >> + png_init_io(write_struct, f); >> + >> + png_set_IHDR(write_struct, info_struct, width, height, 8, >> + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, >> + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); >> + >> + png_write_info(write_struct, info_struct); >> + >> + png_write_image(write_struct, row_pointers); >> + >> + png_write_end(write_struct, NULL); >> + >> + if (fclose(f) != 0) { >> + error_setg(errp, "PNG creation failed. Unable to close file"); >> + return false; >> + } >> + >> + return true; >> +} >> + >> +#else /* no png support */ >> + >> +static bool png_save(int fd, pixman_image_t *image, Error **errp) >> +{ >> + error_setg(errp, "Enable VNC PNG support for png screendump"); >> + return false; >> +} >> + >> +#endif /* CONFIG_VNC_PNG */ >> + >> static bool ppm_save(int fd, pixman_image_t *image, Error **errp) >> { >> int width = pixman_image_get_width(image); >> @@ -327,7 +461,8 @@ static void graphic_hw_update_bh(void *con) >> /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ >> void coroutine_fn >> qmp_screendump(const char *filename, bool has_device, const char *device, >> - bool has_head, int64_t head, Error **errp) >> + bool has_head, int64_t head, bool has_format, >> + const char *format, Error **errp) >> { >> g_autoptr(pixman_image_t) image = NULL; >> QemuConsole *con; >> @@ -383,8 +518,22 @@ qmp_screendump(const char *filename, bool has_device, const char *device, >> * yields and releases the BQL. It could produce corrupted dump, but >> * it should be otherwise safe. >> */ >> - if (!ppm_save(fd, image, errp)) { >> + >> + if (has_format && strcmp(format, "png") == 0) { >> + /* PNG format specified for screendump */ >> + if (!png_save(fd, image, errp)) { >> + qemu_unlink(filename); >> + } >> + } else if (!has_format || (has_format && strcmp(format, "ppm") == 0)) { >> + /* PPM format specified/default for screendump */ >> + if (!ppm_save(fd, image, errp)) { >> + qemu_unlink(filename); >> + } >> + } else { >> + /* Invalid specified for screendump */ >> + error_setg(errp, "Invalid format provided for screendump."); >> qemu_unlink(filename); >> + return; >> } >> } >> >> -- >> 2.22.3 >> >> > Regards, > Daniel Thank you for your prompt review! Regards, Kshitij
On 23/02/22 4:30 pm, Dr. David Alan Gilbert wrote: > * Kshitij Suri (kshitij.suri@nutanix.com) wrote: >> Currently screendump only supports PPM format, which is un-compressed and not >> standard. Added an "format" parameter to qemu monitor screendump capabilites >> to support PNG image capture using libpng. The param was added in QAPI schema >> of screendump present in ui.json along with png_save() function which converts >> pixman_image to PNG. HMP command equivalent was also modified to support the >> feature. >> >> Example usage: >> { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } >> >> Resolves: https://urldefense.proofpoint.com/v2/url?u=https-3A__gitlab.com_qemu-2Dproject_qemu_-2D_issues_718&d=DwIBAg&c=s883GpUCOChKOHiocYtGcg&r=utjv19Ej9Fb0TB7_DX0o3faQ-OAm2ypPniPyqVSoj_w&m=YAoUy9TYXWb8lktv5hZwRWjZEBcoHKxfdrHMd8KkTnQAESANHEcW96C1ukSngzJ2&s=xJP6q9IE0req5UkOFLablyJWWREdmwS1NX4Yse0pYxE&e= >> >> Signed-off-by: Kshitij Suri <kshitij.suri@nutanix.com> >> --- >> hmp-commands.hx | 11 ++-- >> monitor/hmp-cmds.c | 4 +- >> qapi/ui.json | 7 ++- >> ui/console.c | 153 ++++++++++++++++++++++++++++++++++++++++++++- >> 4 files changed, 165 insertions(+), 10 deletions(-) >> >> diff --git a/hmp-commands.hx b/hmp-commands.hx >> index 70a9136ac2..2163337f35 100644 >> --- a/hmp-commands.hx >> +++ b/hmp-commands.hx >> @@ -244,17 +244,18 @@ ERST >> >> { >> .name = "screendump", >> - .args_type = "filename:F,device:s?,head:i?", >> - .params = "filename [device [head]]", >> - .help = "save screen from head 'head' of display device 'device' " >> - "into PPM image 'filename'", >> + .args_type = "filename:F,device:s?,head:i?,format:f?", >> + .params = "filename [device [head]] [format]", >> + .help = "save screen from head 'head' of display device 'device'" >> + "in specified format 'format' as image 'filename'." >> + "Default format for screendump is PPM.", >> .cmd = hmp_screendump, >> .coroutine = true, >> }, >> >> SRST >> ``screendump`` *filename* >> - Save screen into PPM image *filename*. >> + Save screen as image *filename*. >> ERST >> >> { >> diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c >> index 2669156b28..3fb1394561 100644 >> --- a/monitor/hmp-cmds.c >> +++ b/monitor/hmp-cmds.c >> @@ -1665,9 +1665,11 @@ hmp_screendump(Monitor *mon, const QDict *qdict) >> const char *filename = qdict_get_str(qdict, "filename"); >> const char *id = qdict_get_try_str(qdict, "device"); >> int64_t head = qdict_get_try_int(qdict, "head", 0); >> + const char *format = qdict_get_str(qdict, "format"); >> Error *err = NULL; >> >> - qmp_screendump(filename, id != NULL, id, id != NULL, head, &err); >> + qmp_screendump(filename, id != NULL, id, id != NULL, head, >> + format != NULL, format, &err); >> hmp_handle_error(mon, err); >> } > I think that's OK from the HMP front, see some questions below. > >> diff --git a/qapi/ui.json b/qapi/ui.json >> index 9354f4c467..9fdb56b60b 100644 >> --- a/qapi/ui.json >> +++ b/qapi/ui.json >> @@ -76,7 +76,7 @@ >> ## >> # @screendump: >> # >> -# Write a PPM of the VGA screen to a file. >> +# Write a screenshot of the VGA screen to a file. >> # >> # @filename: the path of a new PPM file to store the image >> # >> @@ -87,6 +87,9 @@ >> # parameter is missing, head #0 will be used. Also note that the head >> # can only be specified in conjunction with the device ID. (Since 2.12) >> # >> +# @format: image format for screendump is specified. Currently only PNG and >> +# PPM are supported. >> +# >> # Returns: Nothing on success >> # >> # Since: 0.14 >> @@ -99,7 +102,7 @@ >> # >> ## >> { 'command': 'screendump', >> - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, >> + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', '*format': 'str'}, >> 'coroutine': true } >> >> ## >> diff --git a/ui/console.c b/ui/console.c >> index 40eebb6d2c..7813b195ac 100644 >> --- a/ui/console.c >> +++ b/ui/console.c >> @@ -37,6 +37,9 @@ >> #include "exec/memory.h" >> #include "io/channel-file.h" >> #include "qom/object.h" >> +#ifdef CONFIG_VNC_PNG >> +#include "png.h" >> +#endif >> >> #define DEFAULT_BACKSCROLL 512 >> #define CONSOLE_CURSOR_PERIOD 500 >> @@ -289,6 +292,137 @@ void graphic_hw_invalidate(QemuConsole *con) >> } >> } >> >> +#ifdef CONFIG_VNC_PNG >> +/** >> + * a8r8g8b8_to_rgba: Convert a8r8g8b8 to rgba format >> + * >> + * @dst: Destination pointer. >> + * @src: Source pointer. >> + * @n_pixels: Size of image. >> + */ >> +static void a8r8g8b8_to_rgba(uint32_t *dst, uint32_t *src, int n_pixels) >> +{ >> + uint8_t *dst8 = (uint8_t *)dst; >> + int i; >> + >> + for (i = 0; i < n_pixels; ++i) { >> + uint32_t p = src[i]; >> + uint8_t a, r, g, b; >> + >> + a = (p & 0xff000000) >> 24; >> + r = (p & 0x00ff0000) >> 16; >> + g = (p & 0x0000ff00) >> 8; >> + b = (p & 0x000000ff) >> 0; >> + >> + if (a != 0) { >> + #define DIVIDE(c, a) \ >> + do { \ >> + int t = ((c) * 255) / a; \ >> + (c) = t < 0 ? 0 : t > 255 ? 255 : t; \ > I can't see how 't' can be less than 0 here? > >> + } while (0) >> + >> + DIVIDE(r, a); >> + DIVIDE(g, a); >> + DIVIDE(b, a); >> + #undef DIVIDE >> + } >> + >> + *dst8++ = r; >> + *dst8++ = g; >> + *dst8++ = b; >> + *dst8++ = a; >> + } >> +} > Now, I'm not too much of a graphics person, but I'm a bit confused; this > seems to be applying the alpha scaling to the r/g/b/ data - but then > still including the alpha value in the output; doesn't that mean that > the thing displaying the result will also apply the alpha scaling again? Yes, missed that. Modified it in the updated patch. >> +/** >> + * png_save: Take a screenshot as PNG >> + * >> + * Saves screendump as a PNG file >> + * >> + * Returns true for success or false for error. >> + * Inspired from png test utils from https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_aseprite_pixman&d=DwIBAg&c=s883GpUCOChKOHiocYtGcg&r=utjv19Ej9Fb0TB7_DX0o3faQ-OAm2ypPniPyqVSoj_w&m=YAoUy9TYXWb8lktv5hZwRWjZEBcoHKxfdrHMd8KkTnQAESANHEcW96C1ukSngzJ2&s=WhMqvptTX23UfMHwjTaBDTYU4xqtPO0dvK7B8Tc1nCw&e= >> + * >> + * @fd: File descriptor for PNG file. >> + * @image: Image data in pixman format. >> + * @errp: Pointer to an error. >> + */ >> +static bool png_save(int fd, pixman_image_t *image, Error **errp) >> +{ >> + int width = pixman_image_get_width(image); >> + int height = pixman_image_get_height(image); >> + int stride = width * 4; >> + g_autofree uint32_t *src_data = g_malloc(height * stride); >> + g_autofree uint32_t *dest_data = g_malloc(height * stride); >> + g_autoptr(pixman_image_t) src_copy; >> + g_autoptr(pixman_image_t) dest_copy; >> + g_autofree png_struct *write_struct; >> + g_autofree png_info *info_struct; >> + g_autofree png_bytep *row_pointers = g_malloc(height * sizeof(png_bytep)); >> + FILE *f = fdopen(fd, "wb"); >> + int y; >> + if (!f) { >> + error_setg(errp, "Failed to create file from file descriptor"); >> + return false; >> + } >> + >> + src_copy = pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height, >> + src_data, stride); >> + >> + pixman_image_composite32(PIXMAN_OP_SRC, image, NULL, src_copy, 0, 0, 0, 0, >> + 0, 0, width, height); > Nothing in the rest of qemu uses pixman_image_composite*32* - all the > rest uses the plain version; what's the difference? > >> + memcpy(dest_data, src_data, sizeof(*src_data)); > Why if you're just about to nuke dest_data with the converted version? > >> + a8r8g8b8_to_rgba(dest_data, src_data, height * width); >> + >> + for (y = 0; y < height; ++y) { >> + row_pointers[y] = (png_bytep)(src_data + y * width); >> + } >> + >> + write_struct = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, >> + NULL, NULL); >> + if (!write_struct) { >> + error_setg(errp, "PNG creation failed. Unable to write struct"); >> + return false; >> + } >> + >> + info_struct = png_create_info_struct(write_struct); >> + >> + if (!info_struct) { >> + error_setg(errp, "PNG creation failed. Unable to write info"); >> + return false; >> + } >> + >> + png_init_io(write_struct, f); >> + >> + png_set_IHDR(write_struct, info_struct, width, height, 8, >> + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, >> + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); >> + >> + png_write_info(write_struct, info_struct); >> + >> + png_write_image(write_struct, row_pointers); > Had you considered using png_write_row and avoiding having to > hold/allocate the destination and row_pointers at all? > (In actual fact, can you steal the code in ui/vnc-enc-tight.c > send_png_rect ? ) > > Dave yes thank you for the reference! Updated patch according to vnc-enc-tight.c. >> + png_write_end(write_struct, NULL); >> + >> + if (fclose(f) != 0) { >> + error_setg(errp, "PNG creation failed. Unable to close file"); >> + return false; >> + } >> + >> + return true; >> +} >> + >> +#else /* no png support */ >> + >> +static bool png_save(int fd, pixman_image_t *image, Error **errp) >> +{ >> + error_setg(errp, "Enable VNC PNG support for png screendump"); >> + return false; >> +} >> + >> +#endif /* CONFIG_VNC_PNG */ >> + >> static bool ppm_save(int fd, pixman_image_t *image, Error **errp) >> { >> int width = pixman_image_get_width(image); >> @@ -327,7 +461,8 @@ static void graphic_hw_update_bh(void *con) >> /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ >> void coroutine_fn >> qmp_screendump(const char *filename, bool has_device, const char *device, >> - bool has_head, int64_t head, Error **errp) >> + bool has_head, int64_t head, bool has_format, >> + const char *format, Error **errp) >> { >> g_autoptr(pixman_image_t) image = NULL; >> QemuConsole *con; >> @@ -383,8 +518,22 @@ qmp_screendump(const char *filename, bool has_device, const char *device, >> * yields and releases the BQL. It could produce corrupted dump, but >> * it should be otherwise safe. >> */ >> - if (!ppm_save(fd, image, errp)) { >> + >> + if (has_format && strcmp(format, "png") == 0) { >> + /* PNG format specified for screendump */ >> + if (!png_save(fd, image, errp)) { >> + qemu_unlink(filename); >> + } >> + } else if (!has_format || (has_format && strcmp(format, "ppm") == 0)) { >> + /* PPM format specified/default for screendump */ >> + if (!ppm_save(fd, image, errp)) { >> + qemu_unlink(filename); >> + } >> + } else { >> + /* Invalid specified for screendump */ >> + error_setg(errp, "Invalid format provided for screendump."); >> qemu_unlink(filename); >> + return; >> } >> } >> >> -- >> 2.22.3 >> Thank you for your prompt review! Regards, Kshitij
diff --git a/hmp-commands.hx b/hmp-commands.hx index 70a9136ac2..2163337f35 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -244,17 +244,18 @@ ERST { .name = "screendump", - .args_type = "filename:F,device:s?,head:i?", - .params = "filename [device [head]]", - .help = "save screen from head 'head' of display device 'device' " - "into PPM image 'filename'", + .args_type = "filename:F,device:s?,head:i?,format:f?", + .params = "filename [device [head]] [format]", + .help = "save screen from head 'head' of display device 'device'" + "in specified format 'format' as image 'filename'." + "Default format for screendump is PPM.", .cmd = hmp_screendump, .coroutine = true, }, SRST ``screendump`` *filename* - Save screen into PPM image *filename*. + Save screen as image *filename*. ERST { diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c index 2669156b28..3fb1394561 100644 --- a/monitor/hmp-cmds.c +++ b/monitor/hmp-cmds.c @@ -1665,9 +1665,11 @@ hmp_screendump(Monitor *mon, const QDict *qdict) const char *filename = qdict_get_str(qdict, "filename"); const char *id = qdict_get_try_str(qdict, "device"); int64_t head = qdict_get_try_int(qdict, "head", 0); + const char *format = qdict_get_str(qdict, "format"); Error *err = NULL; - qmp_screendump(filename, id != NULL, id, id != NULL, head, &err); + qmp_screendump(filename, id != NULL, id, id != NULL, head, + format != NULL, format, &err); hmp_handle_error(mon, err); } diff --git a/qapi/ui.json b/qapi/ui.json index 9354f4c467..9fdb56b60b 100644 --- a/qapi/ui.json +++ b/qapi/ui.json @@ -76,7 +76,7 @@ ## # @screendump: # -# Write a PPM of the VGA screen to a file. +# Write a screenshot of the VGA screen to a file. # # @filename: the path of a new PPM file to store the image # @@ -87,6 +87,9 @@ # parameter is missing, head #0 will be used. Also note that the head # can only be specified in conjunction with the device ID. (Since 2.12) # +# @format: image format for screendump is specified. Currently only PNG and +# PPM are supported. +# # Returns: Nothing on success # # Since: 0.14 @@ -99,7 +102,7 @@ # ## { 'command': 'screendump', - 'data': {'filename': 'str', '*device': 'str', '*head': 'int'}, + 'data': {'filename': 'str', '*device': 'str', '*head': 'int', '*format': 'str'}, 'coroutine': true } ## diff --git a/ui/console.c b/ui/console.c index 40eebb6d2c..7813b195ac 100644 --- a/ui/console.c +++ b/ui/console.c @@ -37,6 +37,9 @@ #include "exec/memory.h" #include "io/channel-file.h" #include "qom/object.h" +#ifdef CONFIG_VNC_PNG +#include "png.h" +#endif #define DEFAULT_BACKSCROLL 512 #define CONSOLE_CURSOR_PERIOD 500 @@ -289,6 +292,137 @@ void graphic_hw_invalidate(QemuConsole *con) } } +#ifdef CONFIG_VNC_PNG +/** + * a8r8g8b8_to_rgba: Convert a8r8g8b8 to rgba format + * + * @dst: Destination pointer. + * @src: Source pointer. + * @n_pixels: Size of image. + */ +static void a8r8g8b8_to_rgba(uint32_t *dst, uint32_t *src, int n_pixels) +{ + uint8_t *dst8 = (uint8_t *)dst; + int i; + + for (i = 0; i < n_pixels; ++i) { + uint32_t p = src[i]; + uint8_t a, r, g, b; + + a = (p & 0xff000000) >> 24; + r = (p & 0x00ff0000) >> 16; + g = (p & 0x0000ff00) >> 8; + b = (p & 0x000000ff) >> 0; + + if (a != 0) { + #define DIVIDE(c, a) \ + do { \ + int t = ((c) * 255) / a; \ + (c) = t < 0 ? 0 : t > 255 ? 255 : t; \ + } while (0) + + DIVIDE(r, a); + DIVIDE(g, a); + DIVIDE(b, a); + #undef DIVIDE + } + + *dst8++ = r; + *dst8++ = g; + *dst8++ = b; + *dst8++ = a; + } +} + +/** + * png_save: Take a screenshot as PNG + * + * Saves screendump as a PNG file + * + * Returns true for success or false for error. + * Inspired from png test utils from https://github.com/aseprite/pixman + * + * @fd: File descriptor for PNG file. + * @image: Image data in pixman format. + * @errp: Pointer to an error. + */ +static bool png_save(int fd, pixman_image_t *image, Error **errp) +{ + int width = pixman_image_get_width(image); + int height = pixman_image_get_height(image); + int stride = width * 4; + g_autofree uint32_t *src_data = g_malloc(height * stride); + g_autofree uint32_t *dest_data = g_malloc(height * stride); + g_autoptr(pixman_image_t) src_copy; + g_autoptr(pixman_image_t) dest_copy; + g_autofree png_struct *write_struct; + g_autofree png_info *info_struct; + g_autofree png_bytep *row_pointers = g_malloc(height * sizeof(png_bytep)); + FILE *f = fdopen(fd, "wb"); + int y; + if (!f) { + error_setg(errp, "Failed to create file from file descriptor"); + return false; + } + + src_copy = pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height, + src_data, stride); + + pixman_image_composite32(PIXMAN_OP_SRC, image, NULL, src_copy, 0, 0, 0, 0, + 0, 0, width, height); + + memcpy(dest_data, src_data, sizeof(*src_data)); + + a8r8g8b8_to_rgba(dest_data, src_data, height * width); + + for (y = 0; y < height; ++y) { + row_pointers[y] = (png_bytep)(src_data + y * width); + } + + write_struct = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, + NULL, NULL); + if (!write_struct) { + error_setg(errp, "PNG creation failed. Unable to write struct"); + return false; + } + + info_struct = png_create_info_struct(write_struct); + + if (!info_struct) { + error_setg(errp, "PNG creation failed. Unable to write info"); + return false; + } + + png_init_io(write_struct, f); + + png_set_IHDR(write_struct, info_struct, width, height, 8, + PNG_COLOR_TYPE_RGB_ALPHA, PNG_INTERLACE_NONE, + PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE); + + png_write_info(write_struct, info_struct); + + png_write_image(write_struct, row_pointers); + + png_write_end(write_struct, NULL); + + if (fclose(f) != 0) { + error_setg(errp, "PNG creation failed. Unable to close file"); + return false; + } + + return true; +} + +#else /* no png support */ + +static bool png_save(int fd, pixman_image_t *image, Error **errp) +{ + error_setg(errp, "Enable VNC PNG support for png screendump"); + return false; +} + +#endif /* CONFIG_VNC_PNG */ + static bool ppm_save(int fd, pixman_image_t *image, Error **errp) { int width = pixman_image_get_width(image); @@ -327,7 +461,8 @@ static void graphic_hw_update_bh(void *con) /* Safety: coroutine-only, concurrent-coroutine safe, main thread only */ void coroutine_fn qmp_screendump(const char *filename, bool has_device, const char *device, - bool has_head, int64_t head, Error **errp) + bool has_head, int64_t head, bool has_format, + const char *format, Error **errp) { g_autoptr(pixman_image_t) image = NULL; QemuConsole *con; @@ -383,8 +518,22 @@ qmp_screendump(const char *filename, bool has_device, const char *device, * yields and releases the BQL. It could produce corrupted dump, but * it should be otherwise safe. */ - if (!ppm_save(fd, image, errp)) { + + if (has_format && strcmp(format, "png") == 0) { + /* PNG format specified for screendump */ + if (!png_save(fd, image, errp)) { + qemu_unlink(filename); + } + } else if (!has_format || (has_format && strcmp(format, "ppm") == 0)) { + /* PPM format specified/default for screendump */ + if (!ppm_save(fd, image, errp)) { + qemu_unlink(filename); + } + } else { + /* Invalid specified for screendump */ + error_setg(errp, "Invalid format provided for screendump."); qemu_unlink(filename); + return; } }
Currently screendump only supports PPM format, which is un-compressed and not standard. Added an "format" parameter to qemu monitor screendump capabilites to support PNG image capture using libpng. The param was added in QAPI schema of screendump present in ui.json along with png_save() function which converts pixman_image to PNG. HMP command equivalent was also modified to support the feature. Example usage: { "execute": "screendump", "arguments": { "filename": "/tmp/image", "format":"png" } } Resolves: https://gitlab.com/qemu-project/qemu/-/issues/718 Signed-off-by: Kshitij Suri <kshitij.suri@nutanix.com> --- hmp-commands.hx | 11 ++-- monitor/hmp-cmds.c | 4 +- qapi/ui.json | 7 ++- ui/console.c | 153 ++++++++++++++++++++++++++++++++++++++++++++- 4 files changed, 165 insertions(+), 10 deletions(-)