dec_external_image.h (2875B)
1 // Copyright (c) the JPEG XL Project Authors. All rights reserved. 2 // 3 // Use of this source code is governed by a BSD-style 4 // license that can be found in the LICENSE file. 5 6 #ifndef LIB_JXL_DEC_EXTERNAL_IMAGE_H_ 7 #define LIB_JXL_DEC_EXTERNAL_IMAGE_H_ 8 9 // Interleaved image for color transforms and Codec. 10 11 #include <jxl/types.h> 12 #include <stddef.h> 13 14 #include "lib/jxl/base/data_parallel.h" 15 #include "lib/jxl/base/status.h" 16 #include "lib/jxl/dec_cache.h" 17 #include "lib/jxl/image.h" 18 #include "lib/jxl/image_bundle.h" 19 #include "lib/jxl/image_metadata.h" 20 21 namespace jxl { 22 23 // Maximum number of channels for the ConvertChannelsToExternal function. 24 const size_t kConvertMaxChannels = 4; 25 26 // Converts a list of channels to an interleaved image, applying transformations 27 // when needed. 28 // The input channels are given as a (non-const!) array of channel pointers and 29 // interleaved in that order. 30 // 31 // Note: if a pointer in channels[] is nullptr, a 1.0 value will be used 32 // instead. This is useful for handling when a user requests an alpha channel 33 // from an image that doesn't have one. The first channel in the list may not 34 // be nullptr, since it is used to determine the image size. 35 Status ConvertChannelsToExternal(const ImageF* in_channels[], 36 size_t num_channels, size_t bits_per_sample, 37 bool float_out, JxlEndianness endianness, 38 size_t stride, jxl::ThreadPool* pool, 39 void* out_image, size_t out_size, 40 const PixelCallback& out_callback, 41 jxl::Orientation undo_orientation); 42 43 // Converts ib to interleaved void* pixel buffer with the given format. 44 // bits_per_sample: must be 16 or 32 if float_out is true, and at most 16 45 // if it is false. No bit packing is done. 46 // num_channels: must be 1, 2, 3 or 4 for gray, gray+alpha, RGB, RGB+alpha. 47 // This supports the features needed for the C API and does not perform 48 // color space conversion. 49 // TODO(lode): support rectangle crop. 50 // stride_out is output scanline size in bytes, must be >= 51 // output_xsize * output_bytes_per_pixel. 52 // undo_orientation is an EXIF orientation to undo. Depending on the 53 // orientation, the output xsize and ysize are swapped compared to input 54 // xsize and ysize. 55 Status ConvertToExternal(const jxl::ImageBundle& ib, size_t bits_per_sample, 56 bool float_out, size_t num_channels, 57 JxlEndianness endianness, size_t stride_out, 58 jxl::ThreadPool* thread_pool, void* out_image, 59 size_t out_size, const PixelCallback& out_callback, 60 jxl::Orientation undo_orientation, 61 bool unpremul_alpha = false); 62 63 } // namespace jxl 64 65 #endif // LIB_JXL_DEC_EXTERNAL_IMAGE_H_