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Diffstat (limited to 'third_party/jpeg-xl/lib/jxl/enc_adaptive_quantization.h')
-rw-r--r-- | third_party/jpeg-xl/lib/jxl/enc_adaptive_quantization.h | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/enc_adaptive_quantization.h b/third_party/jpeg-xl/lib/jxl/enc_adaptive_quantization.h new file mode 100644 index 0000000000..6aa8b10df6 --- /dev/null +++ b/third_party/jpeg-xl/lib/jxl/enc_adaptive_quantization.h @@ -0,0 +1,56 @@ +// Copyright (c) the JPEG XL Project Authors. All rights reserved. +// +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +#ifndef LIB_JXL_ENC_ADAPTIVE_QUANTIZATION_H_ +#define LIB_JXL_ENC_ADAPTIVE_QUANTIZATION_H_ + +#include <jxl/cms_interface.h> +#include <stddef.h> + +#include "lib/jxl/ac_strategy.h" +#include "lib/jxl/base/data_parallel.h" +#include "lib/jxl/enc_cache.h" +#include "lib/jxl/frame_header.h" +#include "lib/jxl/image.h" + +// Heuristics to find a good quantizer for a given image. InitialQuantField +// produces a quantization field (i.e. relative quantization amounts for each +// block) out of an opsin-space image. `InitialQuantField` uses heuristics, +// `FindBestQuantizer` (in non-fast mode) will run multiple encoding-decoding +// steps and try to improve the given quant field. + +namespace jxl { + +struct AuxOut; + +// Returns an image subsampled by kBlockDim in each direction. If the value +// at pixel (x,y) in the returned image is greater than 1.0, it means that +// more fine-grained quantization should be used in the corresponding block +// of the input image, while a value less than 1.0 indicates that less +// fine-grained quantization should be enough. Returns a mask, too, which +// can later be used to make better decisions about ac strategy. +ImageF InitialQuantField(float butteraugli_target, const Image3F& opsin, + const Rect& rect, ThreadPool* pool, float rescale, + ImageF* initial_quant_mask, + ImageF* initial_quant_mask1x1); + +float InitialQuantDC(float butteraugli_target); + +void AdjustQuantField(const AcStrategyImage& ac_strategy, const Rect& rect, + float butteraugli_target, ImageF* quant_field); + +// Returns a quantizer that uses an adjusted version of the provided +// quant_field. Also computes the dequant_map corresponding to the given +// dequant_float_map and chosen quantization levels. +// `linear` is only used in Kitten mode or slower. +void FindBestQuantizer(const FrameHeader& frame_header, const Image3F* linear, + const Image3F& opsin, ImageF& quant_field, + PassesEncoderState* enc_state, + const JxlCmsInterface& cms, ThreadPool* pool, + AuxOut* aux_out, double rescale = 1.0); + +} // namespace jxl + +#endif // LIB_JXL_ENC_ADAPTIVE_QUANTIZATION_H_ |