From 5791fdc1cb98b7c1e7ef9cce3405d5e6013fa832 Mon Sep 17 00:00:00 2001 From: Paul Elder Date: Mon, 29 Jun 2020 22:00:53 +0900 Subject: libcamera: formats: Add fields to info to ease calculating stride Packed formats make it difficult to calculate stride as well as frame size with the fields that PixelFormatInfo currently has. bitsPerPixel is defined as the average number of bits per pixel, and only counts effective bits, so it is not useful for calculating stride and frame size. To fix this, we introduce a concept of a "pixel group". The size of this group is defined as the minimum number of pixels (including padding) necessary in a row when the image has only one column of effective pixels. The pixel group has one more attribute, that is the "bytes per group". This determines how many bytes one pixel group consumes. These are the fields pixelsPerGroup and bytesPerGroup that are defined in this patch. Defining these two values makes it really simple to calculate bytes-per-line, as ceil(width / pixelsPerGroup) * bytesPerGroup, where width is measured in number of pixels. The ceiling accounts for padding. The pixel group has another contraint, which is that the pixel group (bytesPerGroup and pixelsPerGroup) is the smallest repeatable unit. What this means is that, for example, in the IPU3 formats, if there is only one column of effective pixels, it looks like it could be fit in 5 bytes with 3 padding pixels (for a total of 4 pixels over 5 bytes). However, this unit is not repeatable, as at the 7th group in the same row, the pattern is broken. Therefore, the pixel group for IPU3 formats must be 25 pixels over 32 bytes. Clearly, pixelsPerGroup must be constant for all planes in the format. The bytesPerGroup then, must be a per-plane attribute. There is one more field, verticalSubSampling, that is per-plane. This is simply a divider, to divide the number of rows of pixels by the sub-sampling value, to obtain the number of rows of pixels for the subsampled plane. For example, for something simple like BGR888, it is self-explanatory: the pixel group size is 1, and the bytes necessary is 3, and there is only one plane with no (= 1) vertical subsampling. For YUYV, the CbCr pair is shared between two pixels, so even if you have only one pixel, you would still need a padded second Y, therefore the pixel group size is 2, and bytes necessary is 4 (as opposed to 1 and 2). YUYV also has no vertical subsampling. NV12 has a pixel group size of 2 pixels, due to the CbCr plane. The bytes per group then, for both planes, is 2. The first plane has no vertical subsampling, but the second plane is subsampled by a factor of 2. The IPU3 formats are also self-explanatory, as they are single-planar, and have a pixel group size of 25, consuming 32 bytes. Although a comment in the driver suggests that it should be 50 and 64, respectively, this is an attribute of the driver, and not the format, so this shall be set by the ipu3 pipeline handler. Signed-off-by: Paul Elder Reviewed-by: Laurent Pinchart Reviewed-by: Jacopo Mondi Reviewed-by: Kieran Bingham --- src/libcamera/formats.cpp | 147 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 147 insertions(+) (limited to 'src') diff --git a/src/libcamera/formats.cpp b/src/libcamera/formats.cpp index d3b722c2..4a03a7e3 100644 --- a/src/libcamera/formats.cpp +++ b/src/libcamera/formats.cpp @@ -110,6 +110,22 @@ const std::map> &ImageFormats::data() const return data_; } +/** + * \class PixelFormatPlaneInfo + * \brief Information about a single plane of a pixel format + * + * \var PixelFormatPlaneInfo::bytesPerGroup + * \brief The number of bytes that a pixel group consumes + * + * \sa PixelFormatInfo::pixelsPerGroup + * + * \var PixelFormatPlaneInfo::verticalSubSampling + * \brief Vertical subsampling multiplier + * + * This value is the ratio between the number of rows of pixels in the frame + * to the number of rows of pixels in the plane. + */ + /** * \class PixelFormatInfo * \brief Information about pixel formats @@ -152,6 +168,48 @@ const std::map> &ImageFormats::data() const * bytes. For instance, 12-bit Bayer data with two pixels stored in three bytes * is packed, while the same data stored with 4 bits of padding in two bytes * per pixel is not packed. + * + * \var PixelFormatInfo::pixelsPerGroup + * \brief The number of pixels in a pixel group + * + * A pixel group is defined as the minimum number of pixels (including padding) + * necessary in a row when the image has only one column of effective pixels. + * pixelsPerGroup refers to this value. PixelFormatPlaneInfo::bytesPerGroup, + * then, refers to the number of bytes that a pixel group consumes. This + * definition of a pixel group allows simple calculation of stride, as + * ceil(width / pixelsPerGroup) * bytesPerGroup. These values are determined + * only in terms of a row. The ceiling accounts for padding. + * + * A pixel group has a second constraint, such that the pixel group + * (bytesPerGroup and pixelsPerGroup) is the smallest repeatable unit. + * What this means is that, for example, in the IPU3 formats, if there is only + * one column of effective pixels, it looks like it could be fit in 5 bytes + * with 3 padding pixels (for a total of 4 pixels over 5 bytes). However, this + * unit is not repeatable, as at the 7th group in the same row, the pattern + * is broken. Therefore, the pixel group for IPU3 formats must be 25 pixels + * over 32 bytes. + * + * For example, for something simple like BGR888, it is self-explanatory: + * the pixel group size is 1, and the bytes necessary is 3, and there is + * only one plane with no (= 1) vertical subsampling. For YUYV, the + * CbCr pair is shared between two pixels, so even if you have only one + * pixel, you would still need a padded second Y sample, therefore the pixel + * group size is 2, and bytes necessary is 4. YUYV also has no vertical + * subsampling. NV12 has a pixel group size of 2 pixels, due to the CbCr plane. + * The bytes per group then, for both planes, is 2. The first plane has no + * vertical subsampling, but the second plane is subsampled by a factor of 2. + * + * The IPU3 raw Bayer formats are single-planar, and have a pixel group size of + * 25, consuming 32 bytes, due to the packing pattern being repeated in memory + * every 32 bytes. The IPU3 hardware, however, has an additional constraint on + * the DMA burst size, requiring lines to be multiple of 64 bytes. This isn't an + * intrinsic property of the formats and is thus not reflected here. It is + * instead enforced by the corresponding pipeline handler. + * + * \var PixelFormatInfo::planes + * \brief Information about pixels for each plane + * + * \sa PixelFormatPlaneInfo */ /** @@ -179,6 +237,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 24, .colourEncoding = PixelFormatInfo::ColourEncodingRGB, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 3, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::RGB888, { .name = "RGB888", @@ -187,6 +247,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 24, .colourEncoding = PixelFormatInfo::ColourEncodingRGB, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 3, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::ABGR8888, { .name = "ABGR8888", @@ -195,6 +257,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 32, .colourEncoding = PixelFormatInfo::ColourEncodingRGB, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::ARGB8888, { .name = "ARGB8888", @@ -203,6 +267,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 32, .colourEncoding = PixelFormatInfo::ColourEncodingRGB, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::BGRA8888, { .name = "BGRA8888", @@ -211,6 +277,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 32, .colourEncoding = PixelFormatInfo::ColourEncodingRGB, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::RGBA8888, { .name = "RGBA8888", @@ -219,6 +287,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 32, .colourEncoding = PixelFormatInfo::ColourEncodingRGB, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, /* YUV packed formats. */ @@ -229,6 +299,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::YVYU, { .name = "YVYU", @@ -237,6 +309,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::UYVY, { .name = "UYVY", @@ -245,6 +319,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::VYUY, { .name = "VYUY", @@ -253,6 +329,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, /* YUV planar formats. */ @@ -263,6 +341,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 2, 2 }, { 0, 0 } }}, } }, { formats::NV21, { .name = "NV21", @@ -271,6 +351,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 2, 2 }, { 0, 0 } }}, } }, { formats::NV16, { .name = "NV16", @@ -279,6 +361,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 2, 1 }, { 0, 0 } }}, } }, { formats::NV61, { .name = "NV61", @@ -287,6 +371,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 2, 1 }, { 0, 0 } }}, } }, { formats::NV24, { .name = "NV24", @@ -295,6 +381,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 24, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 1, 1 }, { 2, 1 }, { 0, 0 } }}, } }, { formats::NV42, { .name = "NV42", @@ -303,6 +391,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 24, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 1, 1 }, { 2, 1 }, { 0, 0 } }}, } }, { formats::YUV420, { .name = "YUV420", @@ -311,6 +401,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 1, 2 }, { 1, 2 } }}, } }, { formats::YUV422, { .name = "YUV422", @@ -319,6 +411,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 16, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 1, 1 }, { 1, 1 } }}, } }, /* Greyscale formats. */ @@ -329,6 +423,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 8, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 1, 1 }, { 0, 0 }, { 0, 0 } }}, } }, /* Bayer formats. */ @@ -339,6 +435,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 8, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGBRG8, { .name = "SGBRG8", @@ -347,6 +445,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 8, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGRBG8, { .name = "SGRBG8", @@ -355,6 +455,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 8, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SRGGB8, { .name = "SRGGB8", @@ -363,6 +465,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 8, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 2, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SBGGR10, { .name = "SBGGR10", @@ -371,6 +475,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGBRG10, { .name = "SGBRG10", @@ -379,6 +485,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGRBG10, { .name = "SGRBG10", @@ -387,6 +495,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SRGGB10, { .name = "SRGGB10", @@ -395,6 +505,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SBGGR10_CSI2P, { .name = "SBGGR10_CSI2P", @@ -403,6 +515,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 4, + .planes = {{ { 5, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGBRG10_CSI2P, { .name = "SGBRG10_CSI2P", @@ -411,6 +525,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 4, + .planes = {{ { 5, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGRBG10_CSI2P, { .name = "SGRBG10_CSI2P", @@ -419,6 +535,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 4, + .planes = {{ { 5, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SRGGB10_CSI2P, { .name = "SRGGB10_CSI2P", @@ -427,6 +545,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 4, + .planes = {{ { 5, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SBGGR12, { .name = "SBGGR12", @@ -435,6 +555,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGBRG12, { .name = "SGBRG12", @@ -443,6 +565,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGRBG12, { .name = "SGRBG12", @@ -451,6 +575,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SRGGB12, { .name = "SRGGB12", @@ -459,6 +585,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = false, + .pixelsPerGroup = 2, + .planes = {{ { 4, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SBGGR12_CSI2P, { .name = "SBGGR12_CSI2P", @@ -467,6 +595,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 2, + .planes = {{ { 3, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGBRG12_CSI2P, { .name = "SGBRG12_CSI2P", @@ -475,6 +605,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 2, + .planes = {{ { 3, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGRBG12_CSI2P, { .name = "SGRBG12_CSI2P", @@ -483,6 +615,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 2, + .planes = {{ { 3, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SRGGB12_CSI2P, { .name = "SRGGB12_CSI2P", @@ -491,6 +625,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 12, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 2, + .planes = {{ { 3, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SBGGR10_IPU3, { .name = "SBGGR10_IPU3", @@ -499,6 +635,9 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + /* \todo remember to double this in the ipu3 pipeline handler */ + .pixelsPerGroup = 25, + .planes = {{ { 32, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGBRG10_IPU3, { .name = "SGBRG10_IPU3", @@ -507,6 +646,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 25, + .planes = {{ { 32, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SGRBG10_IPU3, { .name = "SGRBG10_IPU3", @@ -515,6 +656,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 25, + .planes = {{ { 32, 1 }, { 0, 0 }, { 0, 0 } }}, } }, { formats::SRGGB10_IPU3, { .name = "SRGGB10_IPU3", @@ -523,6 +666,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 10, .colourEncoding = PixelFormatInfo::ColourEncodingRAW, .packed = true, + .pixelsPerGroup = 25, + .planes = {{ { 32, 1 }, { 0, 0 }, { 0, 0 } }}, } }, /* Compressed formats. */ @@ -533,6 +678,8 @@ const std::map pixelFormatInfo{ .bitsPerPixel = 0, .colourEncoding = PixelFormatInfo::ColourEncodingYUV, .packed = false, + .pixelsPerGroup = 1, + .planes = {{ { 1, 1 }, { 0, 0 }, { 0, 0 } }}, } }, }; -- cgit v1.2.1