From patchwork Thu May 2 11:04:59 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 13651616 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 47C546026A for ; Thu, 2 May 2024 11:05:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714647930; cv=none; b=t7z71LK1BJCGK44dqezffWF4mEa4UiemzTAMjvyf9d6y2SAZyTNwxpy3D196MVKXxMDE3IyisoDLqKX9bc8kjrb3oAorr1f2y4+UyftXVPpi0q2Jgp07A8UMHys1ppTPl9WvKXqA85pBDkn7WS1x4C+mro7YMU9+gprLzCC4Yz4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714647930; c=relaxed/simple; bh=hCmaSabMVYRxWhrkkC88YAvIj5fipxLFNvH26VVOkuM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=kWlisrW4Pz5Bkkpsqm6RxsTk8v4DxpFWonO2YzVcquO7zdIB1e04GLdIC9021JLfHyUeKf3wd7VVPfSu8QyIEEWlhddzPUFNePgsF081ANGyluIm2ZK8KMNAVgvXD2/a7S56FMj6uLu288orQy6BowjiKsOJzTexs8R54fTQqHg= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=Q4hp4g5i; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="Q4hp4g5i" Received: from localhost.localdomain (93-61-96-190.ip145.fastwebnet.it [93.61.96.190]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 2FADEDFB; Thu, 2 May 2024 13:04:24 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1714647864; bh=hCmaSabMVYRxWhrkkC88YAvIj5fipxLFNvH26VVOkuM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q4hp4g5itdh7QRSl8J53VYEf7ubCtls421F4z7eX0gBndxNk+HXD9MKpAXxlGD9zh QDwnR9Ek4+PIJcti16A4NPCQODh15lYDk4CmFGXNu9XqeQGKZzx0kfRBuuHkoeswb/ C/gO3hoWKi9kky05ruwoIyXgZQOpk6JXXyYJxF0Y= From: Jacopo Mondi To: Linux Media Mailing List Cc: Jacopo Mondi , David Plowman , Naushir Patuck , Nick Hollinghurst , Dave Stevenson , Tomi Valkeinen , Laurent Pinchart , Kieran Bingham , Sakari Ailus , Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH v6 4/7] media: uapi: Add PiSP Compressed RAW Bayer formats Date: Thu, 2 May 2024 13:04:59 +0200 Message-ID: <20240502110503.38412-5-jacopo.mondi@ideasonboard.com> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240502110503.38412-1-jacopo.mondi@ideasonboard.com> References: <20240502110503.38412-1-jacopo.mondi@ideasonboard.com> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add Raspberry Pi compressed RAW Bayer formats. The compression algorithm description is provided by Nick Hollinghurst from Raspberry Pi. Signed-off-by: Jacopo Mondi Reviewed-by: Naushir Patuck --- .../userspace-api/media/v4l/pixfmt-bayer.rst | 1 + .../media/v4l/pixfmt-srggb8-pisp-comp.rst | 74 +++++++++++++++++++ drivers/media/v4l2-core/v4l2-ioctl.c | 10 +++ include/uapi/linux/videodev2.h | 12 +++ 4 files changed, 97 insertions(+) create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-srggb8-pisp-comp.rst diff --git a/Documentation/userspace-api/media/v4l/pixfmt-bayer.rst b/Documentation/userspace-api/media/v4l/pixfmt-bayer.rst index 2500413e5f43..ed3eb432967d 100644 --- a/Documentation/userspace-api/media/v4l/pixfmt-bayer.rst +++ b/Documentation/userspace-api/media/v4l/pixfmt-bayer.rst @@ -20,6 +20,7 @@ orders. See also `the Wikipedia article on Bayer filter :maxdepth: 1 pixfmt-srggb8 + pixfmt-srggb8-pisp-comp pixfmt-srggb10 pixfmt-srggb10p pixfmt-srggb10alaw8 diff --git a/Documentation/userspace-api/media/v4l/pixfmt-srggb8-pisp-comp.rst b/Documentation/userspace-api/media/v4l/pixfmt-srggb8-pisp-comp.rst new file mode 100644 index 000000000000..ff0fbcf34258 --- /dev/null +++ b/Documentation/userspace-api/media/v4l/pixfmt-srggb8-pisp-comp.rst @@ -0,0 +1,74 @@ +.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later + +.. _v4l2-pix-fmt-pisp-comp1-rggb: +.. _v4l2-pix-fmt-pisp-comp1-grbg: +.. _v4l2-pix-fmt-pisp-comp1-gbrg: +.. _v4l2-pix-fmt-pisp-comp1-bggr: +.. _v4l2-pix-fmt-pisp-comp1-mono: +.. _v4l2-pix-fmt-pisp-comp2-rggb: +.. _v4l2-pix-fmt-pisp-comp2-grbg: +.. _v4l2-pix-fmt-pisp-comp2-gbrg: +.. _v4l2-pix-fmt-pisp-comp2-bggr: +.. _v4l2-pix-fmt-pisp-comp2-mono: + +************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************** +V4L2_PIX_FMT_PISP_COMP1_RGGB ('PC1R'), V4L2_PIX_FMT_PISP_COMP1_GRBG ('PC1G'), V4L2_PIX_FMT_PISP_COMP1_GBRG ('PC1g'), V4L2_PIX_FMT_PISP_COMP1_BGGR ('PC1B), V4L2_PIX_FMT_PISP_COMP1_MONO ('PC1M'), V4L2_PIX_FMT_PISP_COMP2_RGGB ('PC2R'), V4L2_PIX_FMT_PISP_COMP2_GRBG ('PC2G'), V4L2_PIX_FMT_PISP_COMP2_GBRG ('PC2g'), V4L2_PIX_FMT_PISP_COMP2_BGGR ('PC2B), V4L2_PIX_FMT_PISP_COMP2_MONO ('PC2M') +************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************** + +================================================ +Raspberry Pi PiSP compressed 8-bit Bayer formats +================================================ + +Description +=========== + +The Raspberry Pi ISP (PiSP) uses a family of three fixed-rate compressed Bayer +formats. A black-level offset may be subtracted to improve compression +efficiency; the nominal black level and amount of offset must be signalled out +of band. Each scanline is padded to a multiple of 8 pixels wide, and each block +of 8 horizontally-contiguous pixels is coded using 8 bytes. + +Mode 1 uses a quantization and delta-based coding scheme which preserves up to +12 significant bits. Mode 2 is a simple sqrt-like companding scheme with 6 PWL +chords, preserving up to 12 significant bits. Mode 3 combines both companding +(with 4 chords) and the delta scheme, preserving up to 14 significant bits. + +The remainder of this description applies to Modes 1 and 3. + +Each block of 8 pixels is separated into even and odd phases of 4 pixels, +coded independently by 32-bit words at successive locations in memory. +The two LS bits of each 32-bit word give its "quantization mode". + +In quantization mode 0, the lowest 321 quantization levels are multiples of +FSD/4096 and the remaining levels are successive multiples of FSD/2048. +Quantization modes 1 and 2 use linear quantization with step sizes of +FSD/1024 and FSD/512 respectively. Each of the four pixels is quantized +independently, with rounding to the nearest level. +In quantization mode 2 where the middle two samples have quantized values +(q1,q2) both in the range [384..511], they are coded using 9 bits for q1 +followed by 7 bits for (q2 & 127). Otherwise, for quantization modes +0, 1 and 2: a 9-bit field encodes MIN(q1,q2) which must be in the range +[0..511] and a 7-bit field encodes (q2-q1+64) which must be in [0..127]. + +Each of the outer samples (q0,q3) is encoded using a 7-bit field based +on its inner neighbour q1 or q2. In quantization mode 2 where the inner +sample has a quantized value in the range [448..511], the field value is +(q0-384). Otherwise for quantization modes 0, 1 and 2: The outer sample +is encoded as (q0-MAX(0,q1-64)). q3 is likewise coded based on q2. +Each of these values must be in the range [0..127]. All these fields +of 2, 9, 7, 7, 7 bits respectively are packed in little-endian order +to give a 32-bit word with LE byte order. + +Quantization mode 3 has a "7.5-bit" escape, used when none of the above +encodings will fit. Each pixel value is quantized to the nearest of 176 +levels, where the lowest 48 levels are multiples of FSD/256 and the +remaining levels are multiples of FSD/512 (level 175 represents values +very close to FSD and may require saturating arithmetic to decode). + +Each pair of quantized pixels (q0,q1) or (q2,q3) is jointly coded +by a 15-bit field: 2816*(q0>>4) + 16*q1 + (q0&15). +Three fields of 2, 15, 15 bits are packed in LE order {15,15,2}. + +An implementation of a software decoder of compressed formats is available +in `Raspberry Pi camera applications code base +`_. diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c index 7c684788997c..5eb4d797d259 100644 --- a/drivers/media/v4l2-core/v4l2-ioctl.c +++ b/drivers/media/v4l2-core/v4l2-ioctl.c @@ -1532,6 +1532,16 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt) case V4L2_PIX_FMT_MT2110T: descr = "Mediatek 10bit Tile Mode"; break; case V4L2_PIX_FMT_MT2110R: descr = "Mediatek 10bit Raster Mode"; break; case V4L2_PIX_FMT_HEXTILE: descr = "Hextile Compressed Format"; break; + case V4L2_PIX_FMT_PISP_COMP1_RGGB: descr = "PiSP 8b RGRG/GBGB mode1 compr"; break; + case V4L2_PIX_FMT_PISP_COMP1_GRBG: descr = "PiSP 8b GRGR/BGBG mode1 compr"; break; + case V4L2_PIX_FMT_PISP_COMP1_GBRG: descr = "PiSP 8b GBGB/RGRG mode1 compr"; break; + case V4L2_PIX_FMT_PISP_COMP1_BGGR: descr = "PiSP 8b BGBG/GRGR mode1 compr"; break; + case V4L2_PIX_FMT_PISP_COMP1_MONO: descr = "PiSP 8b monochrome mode1 compr"; break; + case V4L2_PIX_FMT_PISP_COMP2_RGGB: descr = "PiSP 8b RGRG/GBGB mode2 compr"; break; + case V4L2_PIX_FMT_PISP_COMP2_GRBG: descr = "PiSP 8b GRGR/BGBG mode2 compr"; break; + case V4L2_PIX_FMT_PISP_COMP2_GBRG: descr = "PiSP 8b GBGB/RGRG mode2 compr"; break; + case V4L2_PIX_FMT_PISP_COMP2_BGGR: descr = "PiSP 8b BGBG/GRGR mode2 compr"; break; + case V4L2_PIX_FMT_PISP_COMP2_MONO: descr = "PiSP 8b monochrome mode2 compr"; break; default: if (fmt->description[0]) return; diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h index 530898b5b342..ab50b7904e0c 100644 --- a/include/uapi/linux/videodev2.h +++ b/include/uapi/linux/videodev2.h @@ -816,6 +816,18 @@ struct v4l2_pix_format { #define V4L2_PIX_FMT_IPU3_SGRBG10 v4l2_fourcc('i', 'p', '3', 'G') /* IPU3 packed 10-bit GRBG bayer */ #define V4L2_PIX_FMT_IPU3_SRGGB10 v4l2_fourcc('i', 'p', '3', 'r') /* IPU3 packed 10-bit RGGB bayer */ +/* Raspberry Pi PiSP compressed formats. */ +#define V4L2_PIX_FMT_PISP_COMP1_RGGB v4l2_fourcc('P', 'C', '1', 'R') /* PiSP 8-bit mode 1 compressed RGGB bayer */ +#define V4L2_PIX_FMT_PISP_COMP1_GRBG v4l2_fourcc('P', 'C', '1', 'G') /* PiSP 8-bit mode 1 compressed GRBG bayer */ +#define V4L2_PIX_FMT_PISP_COMP1_GBRG v4l2_fourcc('P', 'C', '1', 'g') /* PiSP 8-bit mode 1 compressed GBRG bayer */ +#define V4L2_PIX_FMT_PISP_COMP1_BGGR v4l2_fourcc('P', 'C', '1', 'B') /* PiSP 8-bit mode 1 compressed BGGR bayer */ +#define V4L2_PIX_FMT_PISP_COMP1_MONO v4l2_fourcc('P', 'C', '1', 'M') /* PiSP 8-bit mode 1 compressed monochrome */ +#define V4L2_PIX_FMT_PISP_COMP2_RGGB v4l2_fourcc('P', 'C', '2', 'R') /* PiSP 8-bit mode 2 compressed RGGB bayer */ +#define V4L2_PIX_FMT_PISP_COMP2_GRBG v4l2_fourcc('P', 'C', '2', 'G') /* PiSP 8-bit mode 2 compressed GRBG bayer */ +#define V4L2_PIX_FMT_PISP_COMP2_GBRG v4l2_fourcc('P', 'C', '2', 'g') /* PiSP 8-bit mode 2 compressed GBRG bayer */ +#define V4L2_PIX_FMT_PISP_COMP2_BGGR v4l2_fourcc('P', 'C', '2', 'B') /* PiSP 8-bit mode 2 compressed BGGR bayer */ +#define V4L2_PIX_FMT_PISP_COMP2_MONO v4l2_fourcc('P', 'C', '2', 'M') /* PiSP 8-bit mode 2 compressed monochrome */ + /* SDR formats - used only for Software Defined Radio devices */ #define V4L2_SDR_FMT_CU8 v4l2_fourcc('C', 'U', '0', '8') /* IQ u8 */ #define V4L2_SDR_FMT_CU16LE v4l2_fourcc('C', 'U', '1', '6') /* IQ u16le */