diff options
| -rw-r--r-- | src/ipa/ipu3/ipu3.cpp | 70 |
1 files changed, 46 insertions, 24 deletions
diff --git a/src/ipa/ipu3/ipu3.cpp b/src/ipa/ipu3/ipu3.cpp index b3ac96ed..757a5d50 100644 --- a/src/ipa/ipu3/ipu3.cpp +++ b/src/ipa/ipu3/ipu3.cpp @@ -19,6 +19,7 @@ #include <linux/v4l2-controls.h> #include <libcamera/base/log.h> +#include <libcamera/base/utils.h> #include <libcamera/control_ids.h> #include <libcamera/framebuffer.h> @@ -136,8 +137,18 @@ * <linux/intel-ipu3.h> struct ipu3_uapi_gamma_corr_lut for further details. */ -static constexpr uint32_t kMaxCellWidthPerSet = 80; -static constexpr uint32_t kMaxCellHeightPerSet = 60; +/* Minimum grid width, expressed as a number of cells */ +static constexpr uint32_t kMinGridWidth = 16; +/* Maximum grid width, expressed as a number of cells */ +static constexpr uint32_t kMaxGridWidth = 80; +/* Minimum grid height, expressed as a number of cells */ +static constexpr uint32_t kMinGridHeight = 16; +/* Maximum grid height, expressed as a number of cells */ +static constexpr uint32_t kMaxGridHeight = 60; +/* log2 of the minimum grid cell width and height, in pixels */ +static constexpr uint32_t kMinCellSizeLog2 = 3; +/* log2 of the maximum grid cell width and height, in pixels */ +static constexpr uint32_t kMaxCellSizeLog2 = 6; namespace libcamera { @@ -281,45 +292,56 @@ int IPAIPU3::start() } /** + * \brief Calculate a grid for the AWB statistics + * * This function calculates a grid for the AWB algorithm in the IPU3 firmware. * Its input is the BDS output size calculated in the ImgU. * It is limited for now to the simplest method: find the lesser error * with the width/height and respective log2 width/height of the cells. * - * \todo The frame is divided into cells which can be 8x8 => 128x128. + * \todo The frame is divided into cells which can be 8x8 => 64x64. * As a smaller cell improves the algorithm precision, adapting the * x_start and y_start parameters of the grid would provoke a loss of * some pixels but would also result in more accurate algorithms. */ void IPAIPU3::calculateBdsGrid(const Size &bdsOutputSize) { - uint32_t minError = std::numeric_limits<uint32_t>::max(); Size best; Size bestLog2; /* Set the BDS output size in the IPAConfiguration structure */ context_.configuration.grid.bdsOutputSize = bdsOutputSize; - for (uint32_t widthShift = 3; widthShift <= 6; ++widthShift) { - uint32_t width = std::min(kMaxCellWidthPerSet, - bdsOutputSize.width >> widthShift); - width = width << widthShift; - for (uint32_t heightShift = 3; heightShift <= 6; ++heightShift) { - int32_t height = std::min(kMaxCellHeightPerSet, - bdsOutputSize.height >> heightShift); - height = height << heightShift; - uint32_t error = std::abs(static_cast<int>(width - bdsOutputSize.width)) - + std::abs(static_cast<int>(height - bdsOutputSize.height)); - - if (error > minError) - continue; - - minError = error; - best.width = width; - best.height = height; - bestLog2.width = widthShift; - bestLog2.height = heightShift; - } + uint32_t minError = std::numeric_limits<uint32_t>::max(); + for (uint32_t shift = kMinCellSizeLog2; shift <= kMaxCellSizeLog2; ++shift) { + uint32_t width = std::clamp(bdsOutputSize.width >> shift, + kMinGridWidth, + kMaxGridWidth); + + width = width << shift; + uint32_t error = std::abs(static_cast<int>(width - bdsOutputSize.width)); + if (error >= minError) + continue; + + minError = error; + best.width = width; + bestLog2.width = shift; + } + + minError = std::numeric_limits<uint32_t>::max(); + for (uint32_t shift = kMinCellSizeLog2; shift <= kMaxCellSizeLog2; ++shift) { + uint32_t height = std::clamp(bdsOutputSize.height >> shift, + kMinGridHeight, + kMaxGridHeight); + + height = height << shift; + uint32_t error = std::abs(static_cast<int>(height - bdsOutputSize.height)); + if (error >= minError) + continue; + + minError = error; + best.height = height; + bestLog2.height = shift; } struct ipu3_uapi_grid_config &bdsGrid = context_.configuration.grid.bdsGrid; |