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5efd6300dc
There's no need for this in libsharpyuv currently. This avoids an ABI bump and library size increase. Change-Id: I3e4c79052fdb4d628a2d36491547233dd0b6dc34
111 lines
5.1 KiB
C
111 lines
5.1 KiB
C
// Copyright 2015 Google Inc. All Rights Reserved.
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//
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// Use of this source code is governed by a BSD-style license
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// that can be found in the COPYING file in the root of the source
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// tree. An additional intellectual property rights grant can be found
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// in the file PATENTS. All contributing project authors may
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// be found in the AUTHORS file in the root of the source tree.
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// -----------------------------------------------------------------------------
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//
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#ifndef WEBP_EXTRAS_EXTRAS_H_
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#define WEBP_EXTRAS_EXTRAS_H_
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#include "webp/types.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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#include "sharpyuv/sharpyuv.h"
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#include "webp/encode.h"
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#define WEBP_EXTRAS_ABI_VERSION 0x0003 // MAJOR(8b) + MINOR(8b)
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//------------------------------------------------------------------------------
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// Returns the version number of the extras library, packed in hexadecimal using
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// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
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WEBP_EXTERN int WebPGetExtrasVersion(void);
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//------------------------------------------------------------------------------
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// Ad-hoc colorspace importers.
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// Import luma sample (gray scale image) into 'picture'. The 'picture'
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// width and height must be set prior to calling this function.
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WEBP_EXTERN int WebPImportGray(const uint8_t* gray, WebPPicture* picture);
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// Import rgb sample in RGB565 packed format into 'picture'. The 'picture'
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// width and height must be set prior to calling this function.
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WEBP_EXTERN int WebPImportRGB565(const uint8_t* rgb565, WebPPicture* pic);
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// Import rgb sample in RGB4444 packed format into 'picture'. The 'picture'
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// width and height must be set prior to calling this function.
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WEBP_EXTERN int WebPImportRGB4444(const uint8_t* rgb4444, WebPPicture* pic);
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// Import a color mapped image. The number of colors is less or equal to
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// MAX_PALETTE_SIZE. 'pic' must have been initialized. Its content, if any,
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// will be discarded. Returns 'false' in case of error, or if indexed[] contains
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// invalid indices.
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WEBP_EXTERN int
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WebPImportColorMappedARGB(const uint8_t* indexed, int indexed_stride,
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const uint32_t palette[], int palette_size,
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WebPPicture* pic);
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// Convert the ARGB content of 'pic' from associated to unassociated.
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// 'pic' can be for instance the result of calling of some WebPPictureImportXXX
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// functions, with pic->use_argb set to 'true'. It is assumed (and not checked)
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// that the pre-multiplied r/g/b values as less or equal than the alpha value.
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// Return false in case of error (invalid parameter, ...).
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WEBP_EXTERN int WebPUnmultiplyARGB(WebPPicture* pic);
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//------------------------------------------------------------------------------
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// Parse a bitstream, search for VP8 (lossy) header and report a
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// rough estimation of the quality factor used for compressing the bitstream.
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// If the bitstream is in lossless format, the special value '101' is returned.
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// Otherwise (lossy bitstream), the returned value is in the range [0..100].
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// Any error (invalid bitstream, animated WebP, incomplete header, etc.)
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// will return a value of -1.
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WEBP_EXTERN int VP8EstimateQuality(const uint8_t* const data, size_t size);
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//------------------------------------------------------------------------------
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// Computes a score between 0 and 100 which represents the risk of having visual
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// quality loss from converting an RGB image to YUV420.
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// A low score, typically < 40, means there is a low risk of artifacts from
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// chroma subsampling and a simple averaging algorithm can be used instead of
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// the more expensive SharpYuvConvert function.
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// A medium score, typically >= 40 and < 70, means that simple chroma
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// subsampling will produce artifacts and it may be advisable to use the more
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// costly SharpYuvConvert for YUV420 conversion.
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// A high score, typically >= 70, means there is a very high risk of artifacts
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// from chroma subsampling even with SharpYuvConvert, and best results might be
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// achieved by using YUV444.
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// If not using SharpYuvConvert, a threshold of about 50 can be used to decide
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// between (simple averaging) 420 and 444.
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// r_ptr, g_ptr, b_ptr: pointers to the source r, g and b channels. Should point
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// to uint8_t buffers if rgb_bit_depth is 8, or uint16_t buffers otherwise.
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// rgb_step: distance in bytes between two horizontally adjacent pixels on the
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// r, g and b channels. If rgb_bit_depth is > 8, it should be a
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// multiple of 2.
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// rgb_stride: distance in bytes between two vertically adjacent pixels on the
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// r, g, and b channels. If rgb_bit_depth is > 8, it should be a
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// multiple of 2.
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// rgb_bit_depth: number of bits for each r/g/b value. Only a value of 8 is
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// currently supported.
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// width, height: width and height of the image in pixels
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// Returns 0 on failure.
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WEBP_EXTERN int SharpYuvEstimate420Risk(
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const void* r_ptr, const void* g_ptr, const void* b_ptr, int rgb_step,
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int rgb_stride, int rgb_bit_depth, int width, int height,
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const SharpYuvOptions* options, float* score);
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//------------------------------------------------------------------------------
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#ifdef __cplusplus
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} // extern "C"
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#endif
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#endif // WEBP_EXTRAS_EXTRAS_H_
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