1793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Copyright 2010 Google Inc. All Rights Reserved. 2793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// 3793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Use of this source code is governed by a BSD-style license 4793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// that can be found in the COPYING file in the root of the source 5793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// tree. An additional intellectual property rights grant can be found 6793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// in the file PATENTS. All contributing project authors may 7793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// be found in the AUTHORS file in the root of the source tree. 8793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// ----------------------------------------------------------------------------- 9793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// 10793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Low-level API for VP8 decoder 11793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// 12793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Author: Skal (pascal.massimino@gmail.com) 13793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 14793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#ifndef WEBP_WEBP_DECODE_VP8_H_ 15793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#define WEBP_WEBP_DECODE_VP8_H_ 16793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 17793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#include "../webp/decode.h" 18793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 19793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#if defined(__cplusplus) || defined(c_plusplus) 20793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerextern "C" { 21793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#endif 22793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 23793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler//------------------------------------------------------------------------------ 24793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Lower-level API 25793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// 26793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// These functions provide fine-grained control of the decoding process. 27793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// The call flow should resemble: 28793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// 29793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// VP8Io io; 30793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// VP8InitIo(&io); 31793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// io.data = data; 32793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// io.data_size = size; 33793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// /* customize io's functions (setup()/put()/teardown()) if needed. */ 34793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// 35793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// VP8Decoder* dec = VP8New(); 36793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// bool ok = VP8Decode(dec); 37793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// if (!ok) printf("Error: %s\n", VP8StatusMessage(dec)); 38793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// VP8Delete(dec); 39793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// return ok; 40793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 41793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Input / Output 42793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslertypedef struct VP8Io VP8Io; 43793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslertypedef int (*VP8IoPutHook)(const VP8Io* io); 44793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslertypedef int (*VP8IoSetupHook)(VP8Io* io); 45793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslertypedef void (*VP8IoTeardownHook)(const VP8Io* io); 46793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 47793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerstruct VP8Io { 48793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // set by VP8GetHeaders() 49793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int width, height; // picture dimensions, in pixels (invariable). 50793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // These are the original, uncropped dimensions. 51793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // The actual area passed to put() is stored 52793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // in mb_w / mb_h fields. 53793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 54793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // set before calling put() 55793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int mb_y; // position of the current rows (in pixels) 56793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int mb_w; // number of columns in the sample 57793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int mb_h; // number of rows in the sample 58793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler const uint8_t* y, *u, *v; // rows to copy (in yuv420 format) 59793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int y_stride; // row stride for luma 60793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int uv_stride; // row stride for chroma 61793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 62793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler void* opaque; // user data 63793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 64793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // called when fresh samples are available. Currently, samples are in 65793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // YUV420 format, and can be up to width x 24 in size (depending on the 66793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // in-loop filtering level, e.g.). Should return false in case of error 67793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // or abort request. The actual size of the area to update is mb_w x mb_h 68793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // in size, taking cropping into account. 69793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler VP8IoPutHook put; 70793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 71793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // called just before starting to decode the blocks. 72793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // Must return false in case of setup error, true otherwise. If false is 73793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // returned, teardown() will NOT be called. But if the setup succeeded 74793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // and true is returned, then teardown() will always be called afterward. 75793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler VP8IoSetupHook setup; 76793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 77793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // Called just after block decoding is finished (or when an error occurred 78793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // during put()). Is NOT called if setup() failed. 79793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler VP8IoTeardownHook teardown; 80793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 81793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // this is a recommendation for the user-side yuv->rgb converter. This flag 82793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // is set when calling setup() hook and can be overwritten by it. It then 83793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // can be taken into consideration during the put() method. 84793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int fancy_upsampling; 85793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 86793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // Input buffer. 87793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler size_t data_size; 88793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler const uint8_t* data; 89793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 90793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // If true, in-loop filtering will not be performed even if present in the 91793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // bitstream. Switching off filtering may speed up decoding at the expense 92793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // of more visible blocking. Note that output will also be non-compliant 93793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // with the VP8 specifications. 94793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int bypass_filtering; 95793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 96793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // Cropping parameters. 97793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int use_cropping; 98793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int crop_left, crop_right, crop_top, crop_bottom; 99793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 100793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // Scaling parameters. 101793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int use_scaling; 102793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int scaled_width, scaled_height; 103793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 104793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // If non NULL, pointer to the alpha data (if present) corresponding to the 105793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // start of the current row (That is: it is pre-offset by mb_y and takes 106793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler // cropping into account). 107793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler const uint8_t* a; 108793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler}; 109793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 110793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Internal, version-checked, entry point 111793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerint VP8InitIoInternal(VP8Io* const, int); 112793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 113793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Set the custom IO function pointers and user-data. The setter for IO hooks 114793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// should be called before initiating incremental decoding. Returns true if 115793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// WebPIDecoder object is successfully modified, false otherwise. 116793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerint WebPISetIOHooks(WebPIDecoder* const idec, 117793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler VP8IoPutHook put, 118793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler VP8IoSetupHook setup, 119793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler VP8IoTeardownHook teardown, 120793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler void* user_data); 121793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 122793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Main decoding object. This is an opaque structure. 123793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslertypedef struct VP8Decoder VP8Decoder; 124793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 125793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Create a new decoder object. 126793ee12c6df9cad3806238d32528c49a3ff9331dNoah PreslerVP8Decoder* VP8New(void); 127793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 128793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Must be called to make sure 'io' is initialized properly. 129793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Returns false in case of version mismatch. Upon such failure, no other 130793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// decoding function should be called (VP8Decode, VP8GetHeaders, ...) 131793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerstatic WEBP_INLINE int VP8InitIo(VP8Io* const io) { 132793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler return VP8InitIoInternal(io, WEBP_DECODER_ABI_VERSION); 133793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler} 134793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 135793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Start decoding a new picture. Returns true if ok. 136793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerint VP8GetHeaders(VP8Decoder* const dec, VP8Io* const io); 137793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 138793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Decode a picture. Will call VP8GetHeaders() if it wasn't done already. 139793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Returns false in case of error. 140793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerint VP8Decode(VP8Decoder* const dec, VP8Io* const io); 141793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 142793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Return current status of the decoder: 143793ee12c6df9cad3806238d32528c49a3ff9331dNoah PreslerVP8StatusCode VP8Status(VP8Decoder* const dec); 144793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 145793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// return readable string corresponding to the last status. 146793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslerconst char* VP8StatusMessage(VP8Decoder* const dec); 147793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 148793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Resets the decoder in its initial state, reclaiming memory. 149793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Not a mandatory call between calls to VP8Decode(). 150793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslervoid VP8Clear(VP8Decoder* const dec); 151793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 152793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Destroy the decoder object. 153793ee12c6df9cad3806238d32528c49a3ff9331dNoah Preslervoid VP8Delete(VP8Decoder* const dec); 154793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 155793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler//------------------------------------------------------------------------------ 156793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Miscellaneous VP8/VP8L bitstream probing functions. 157793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 158793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Returns true if the next 3 bytes in data contain the VP8 signature. 159793ee12c6df9cad3806238d32528c49a3ff9331dNoah PreslerWEBP_EXTERN(int) VP8CheckSignature(const uint8_t* const data, size_t data_size); 160793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 161793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Validates the VP8 data-header and retrieves basic header information viz 162793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// width and height. Returns 0 in case of formatting error. *width/*height 163793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// can be passed NULL. 164793ee12c6df9cad3806238d32528c49a3ff9331dNoah PreslerWEBP_EXTERN(int) VP8GetInfo( 165793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler const uint8_t* data, 166793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler size_t data_size, // data available so far 167793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler size_t chunk_size, // total data size expected in the chunk 168793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int* const width, int* const height); 169793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 170793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Returns true if the next byte(s) in data is a VP8L signature. 171793ee12c6df9cad3806238d32528c49a3ff9331dNoah PreslerWEBP_EXTERN(int) VP8LCheckSignature(const uint8_t* const data, size_t size); 172793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 173793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// Validates the VP8L data-header and retrieves basic header information viz 174793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// width, height and alpha. Returns 0 in case of formatting error. 175793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler// width/height/has_alpha can be passed NULL. 176793ee12c6df9cad3806238d32528c49a3ff9331dNoah PreslerWEBP_EXTERN(int) VP8LGetInfo( 177793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler const uint8_t* data, size_t data_size, // data available so far 178793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler int* const width, int* const height, int* const has_alpha); 179793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 180793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#if defined(__cplusplus) || defined(c_plusplus) 181793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler} // extern "C" 182793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#endif 183793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler 184793ee12c6df9cad3806238d32528c49a3ff9331dNoah Presler#endif /* WEBP_WEBP_DECODE_VP8_H_ */ 185