531 lines
22 KiB
C++
531 lines
22 KiB
C++
// Copyright 2011 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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// RIFF container manipulation and encoding for WebP images.
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//
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// Authors: Urvang (urvang@google.com)
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// Vikas (vikasa@google.com)
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#ifndef WEBP_WEBP_MUX_H_
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#define WEBP_WEBP_MUX_H_
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#include "./mux_types.h"
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#ifdef __cplusplus
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extern "C" {
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#endif
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#define WEBP_MUX_ABI_VERSION 0x0108 // MAJOR(8b) + MINOR(8b)
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//------------------------------------------------------------------------------
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// Mux API
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//
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// This API allows manipulation of WebP container images containing features
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// like color profile, metadata, animation.
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//
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// Code Example#1: Create a WebPMux object with image data, color profile and
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// XMP metadata.
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/*
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int copy_data = 0;
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WebPMux* mux = WebPMuxNew();
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// ... (Prepare image data).
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WebPMuxSetImage(mux, &image, copy_data);
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// ... (Prepare ICCP color profile data).
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WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
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// ... (Prepare XMP metadata).
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WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
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// Get data from mux in WebP RIFF format.
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WebPMuxAssemble(mux, &output_data);
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WebPMuxDelete(mux);
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// ... (Consume output_data; e.g. write output_data.bytes to file).
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WebPDataClear(&output_data);
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*/
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// Code Example#2: Get image and color profile data from a WebP file.
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/*
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int copy_data = 0;
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// ... (Read data from file).
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WebPMux* mux = WebPMuxCreate(&data, copy_data);
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WebPMuxGetFrame(mux, 1, &image);
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// ... (Consume image; e.g. call WebPDecode() to decode the data).
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WebPMuxGetChunk(mux, "ICCP", &icc_profile);
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// ... (Consume icc_data).
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WebPMuxDelete(mux);
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free(data);
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*/
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// Note: forward declaring enumerations is not allowed in (strict) C and C++,
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// the types are left here for reference.
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// typedef enum WebPMuxError WebPMuxError;
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// typedef enum WebPChunkId WebPChunkId;
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typedef struct WebPMux WebPMux; // main opaque object.
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typedef struct WebPMuxFrameInfo WebPMuxFrameInfo;
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typedef struct WebPMuxAnimParams WebPMuxAnimParams;
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typedef struct WebPAnimEncoderOptions WebPAnimEncoderOptions;
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// Error codes
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typedef enum WebPMuxError {
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WEBP_MUX_OK = 1,
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WEBP_MUX_NOT_FOUND = 0,
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WEBP_MUX_INVALID_ARGUMENT = -1,
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WEBP_MUX_BAD_DATA = -2,
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WEBP_MUX_MEMORY_ERROR = -3,
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WEBP_MUX_NOT_ENOUGH_DATA = -4
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} WebPMuxError;
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// IDs for different types of chunks.
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typedef enum WebPChunkId {
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WEBP_CHUNK_VP8X, // VP8X
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WEBP_CHUNK_ICCP, // ICCP
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WEBP_CHUNK_ANIM, // ANIM
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WEBP_CHUNK_ANMF, // ANMF
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WEBP_CHUNK_DEPRECATED, // (deprecated from FRGM)
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WEBP_CHUNK_ALPHA, // ALPH
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WEBP_CHUNK_IMAGE, // VP8/VP8L
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WEBP_CHUNK_EXIF, // EXIF
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WEBP_CHUNK_XMP, // XMP
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WEBP_CHUNK_UNKNOWN, // Other chunks.
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WEBP_CHUNK_NIL
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} WebPChunkId;
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//------------------------------------------------------------------------------
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// Returns the version number of the mux 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) WebPGetMuxVersion(void);
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//------------------------------------------------------------------------------
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// Life of a Mux object
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// Internal, version-checked, entry point
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WEBP_EXTERN(WebPMux*) WebPNewInternal(int);
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// Creates an empty mux object.
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// Returns:
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// A pointer to the newly created empty mux object.
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// Or NULL in case of memory error.
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static WEBP_INLINE WebPMux* WebPMuxNew(void) {
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return WebPNewInternal(WEBP_MUX_ABI_VERSION);
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}
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// Deletes the mux object.
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// Parameters:
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// mux - (in/out) object to be deleted
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WEBP_EXTERN(void) WebPMuxDelete(WebPMux* mux);
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//------------------------------------------------------------------------------
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// Mux creation.
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// Internal, version-checked, entry point
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WEBP_EXTERN(WebPMux*) WebPMuxCreateInternal(const WebPData*, int, int);
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// Creates a mux object from raw data given in WebP RIFF format.
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// Parameters:
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// bitstream - (in) the bitstream data in WebP RIFF format
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// copy_data - (in) value 1 indicates given data WILL be copied to the mux
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// object and value 0 indicates data will NOT be copied.
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// Returns:
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// A pointer to the mux object created from given data - on success.
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// NULL - In case of invalid data or memory error.
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static WEBP_INLINE WebPMux* WebPMuxCreate(const WebPData* bitstream,
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int copy_data) {
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return WebPMuxCreateInternal(bitstream, copy_data, WEBP_MUX_ABI_VERSION);
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}
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//------------------------------------------------------------------------------
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// Non-image chunks.
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// Note: Only non-image related chunks should be managed through chunk APIs.
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// (Image related chunks are: "ANMF", "VP8 ", "VP8L" and "ALPH").
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// To add, get and delete images, use WebPMuxSetImage(), WebPMuxPushFrame(),
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// WebPMuxGetFrame() and WebPMuxDeleteFrame().
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// Adds a chunk with id 'fourcc' and data 'chunk_data' in the mux object.
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// Any existing chunk(s) with the same id will be removed.
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// Parameters:
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// mux - (in/out) object to which the chunk is to be added
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// fourcc - (in) a character array containing the fourcc of the given chunk;
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// e.g., "ICCP", "XMP ", "EXIF" etc.
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// chunk_data - (in) the chunk data to be added
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// copy_data - (in) value 1 indicates given data WILL be copied to the mux
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// object and value 0 indicates data will NOT be copied.
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux, fourcc or chunk_data is NULL
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// or if fourcc corresponds to an image chunk.
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// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxSetChunk(
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WebPMux* mux, const char fourcc[4], const WebPData* chunk_data,
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int copy_data);
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// Gets a reference to the data of the chunk with id 'fourcc' in the mux object.
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// The caller should NOT free the returned data.
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// Parameters:
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// mux - (in) object from which the chunk data is to be fetched
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// fourcc - (in) a character array containing the fourcc of the chunk;
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// e.g., "ICCP", "XMP ", "EXIF" etc.
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// chunk_data - (out) returned chunk data
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux, fourcc or chunk_data is NULL
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// or if fourcc corresponds to an image chunk.
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// WEBP_MUX_NOT_FOUND - If mux does not contain a chunk with the given id.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxGetChunk(
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const WebPMux* mux, const char fourcc[4], WebPData* chunk_data);
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// Deletes the chunk with the given 'fourcc' from the mux object.
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// Parameters:
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// mux - (in/out) object from which the chunk is to be deleted
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// fourcc - (in) a character array containing the fourcc of the chunk;
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// e.g., "ICCP", "XMP ", "EXIF" etc.
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux or fourcc is NULL
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// or if fourcc corresponds to an image chunk.
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// WEBP_MUX_NOT_FOUND - If mux does not contain a chunk with the given fourcc.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxDeleteChunk(
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WebPMux* mux, const char fourcc[4]);
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//------------------------------------------------------------------------------
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// Images.
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// Encapsulates data about a single frame.
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struct WebPMuxFrameInfo {
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WebPData bitstream; // image data: can be a raw VP8/VP8L bitstream
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// or a single-image WebP file.
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int x_offset; // x-offset of the frame.
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int y_offset; // y-offset of the frame.
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int duration; // duration of the frame (in milliseconds).
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WebPChunkId id; // frame type: should be one of WEBP_CHUNK_ANMF
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// or WEBP_CHUNK_IMAGE
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WebPMuxAnimDispose dispose_method; // Disposal method for the frame.
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WebPMuxAnimBlend blend_method; // Blend operation for the frame.
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uint32_t pad[1]; // padding for later use
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};
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// Sets the (non-animated) image in the mux object.
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// Note: Any existing images (including frames) will be removed.
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// Parameters:
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// mux - (in/out) object in which the image is to be set
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// bitstream - (in) can be a raw VP8/VP8L bitstream or a single-image
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// WebP file (non-animated)
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// copy_data - (in) value 1 indicates given data WILL be copied to the mux
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// object and value 0 indicates data will NOT be copied.
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL or bitstream is NULL.
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// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxSetImage(
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WebPMux* mux, const WebPData* bitstream, int copy_data);
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// Adds a frame at the end of the mux object.
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// Notes: (1) frame.id should be WEBP_CHUNK_ANMF
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// (2) For setting a non-animated image, use WebPMuxSetImage() instead.
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// (3) Type of frame being pushed must be same as the frames in mux.
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// (4) As WebP only supports even offsets, any odd offset will be snapped
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// to an even location using: offset &= ~1
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// Parameters:
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// mux - (in/out) object to which the frame is to be added
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// frame - (in) frame data.
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// copy_data - (in) value 1 indicates given data WILL be copied to the mux
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// object and value 0 indicates data will NOT be copied.
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux or frame is NULL
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// or if content of 'frame' is invalid.
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// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxPushFrame(
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WebPMux* mux, const WebPMuxFrameInfo* frame, int copy_data);
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// Gets the nth frame from the mux object.
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// The content of 'frame->bitstream' is allocated using malloc(), and NOT
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// owned by the 'mux' object. It MUST be deallocated by the caller by calling
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// WebPDataClear().
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// nth=0 has a special meaning - last position.
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// Parameters:
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// mux - (in) object from which the info is to be fetched
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// nth - (in) index of the frame in the mux object
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// frame - (out) data of the returned frame
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux or frame is NULL.
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// WEBP_MUX_NOT_FOUND - if there are less than nth frames in the mux object.
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// WEBP_MUX_BAD_DATA - if nth frame chunk in mux is invalid.
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// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxGetFrame(
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const WebPMux* mux, uint32_t nth, WebPMuxFrameInfo* frame);
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// Deletes a frame from the mux object.
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// nth=0 has a special meaning - last position.
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// Parameters:
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// mux - (in/out) object from which a frame is to be deleted
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// nth - (in) The position from which the frame is to be deleted
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL.
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// WEBP_MUX_NOT_FOUND - If there are less than nth frames in the mux object
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// before deletion.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxDeleteFrame(WebPMux* mux, uint32_t nth);
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//------------------------------------------------------------------------------
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// Animation.
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// Animation parameters.
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struct WebPMuxAnimParams {
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uint32_t bgcolor; // Background color of the canvas stored (in MSB order) as:
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// Bits 00 to 07: Alpha.
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// Bits 08 to 15: Red.
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// Bits 16 to 23: Green.
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// Bits 24 to 31: Blue.
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int loop_count; // Number of times to repeat the animation [0 = infinite].
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};
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// Sets the animation parameters in the mux object. Any existing ANIM chunks
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// will be removed.
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// Parameters:
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// mux - (in/out) object in which ANIM chunk is to be set/added
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// params - (in) animation parameters.
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
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// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxSetAnimationParams(
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WebPMux* mux, const WebPMuxAnimParams* params);
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// Gets the animation parameters from the mux object.
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// Parameters:
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// mux - (in) object from which the animation parameters to be fetched
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// params - (out) animation parameters extracted from the ANIM chunk
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
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// WEBP_MUX_NOT_FOUND - if ANIM chunk is not present in mux object.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxGetAnimationParams(
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const WebPMux* mux, WebPMuxAnimParams* params);
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//------------------------------------------------------------------------------
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// Misc Utilities.
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// Sets the canvas size for the mux object. The width and height can be
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// specified explicitly or left as zero (0, 0).
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// * When width and height are specified explicitly, then this frame bound is
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// enforced during subsequent calls to WebPMuxAssemble() and an error is
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// reported if any animated frame does not completely fit within the canvas.
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// * When unspecified (0, 0), the constructed canvas will get the frame bounds
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// from the bounding-box over all frames after calling WebPMuxAssemble().
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// Parameters:
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// mux - (in) object to which the canvas size is to be set
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// width - (in) canvas width
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// height - (in) canvas height
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux is NULL; or
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// width or height are invalid or out of bounds
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxSetCanvasSize(WebPMux* mux,
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int width, int height);
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// Gets the canvas size from the mux object.
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// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
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// That is, the mux object hasn't been modified since the last call to
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// WebPMuxAssemble() or WebPMuxCreate().
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// Parameters:
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// mux - (in) object from which the canvas size is to be fetched
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// width - (out) canvas width
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// height - (out) canvas height
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux, width or height is NULL.
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// WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxGetCanvasSize(const WebPMux* mux,
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int* width, int* height);
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// Gets the feature flags from the mux object.
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// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
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// That is, the mux object hasn't been modified since the last call to
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// WebPMuxAssemble() or WebPMuxCreate().
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// Parameters:
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// mux - (in) object from which the features are to be fetched
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// flags - (out) the flags specifying which features are present in the
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// mux object. This will be an OR of various flag values.
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// Enum 'WebPFeatureFlags' can be used to test individual flag values.
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux or flags is NULL.
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// WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxGetFeatures(const WebPMux* mux,
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uint32_t* flags);
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// Gets number of chunks with the given 'id' in the mux object.
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// Parameters:
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// mux - (in) object from which the info is to be fetched
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// id - (in) chunk id specifying the type of chunk
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// num_elements - (out) number of chunks with the given chunk id
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// Returns:
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// WEBP_MUX_INVALID_ARGUMENT - if mux, or num_elements is NULL.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxNumChunks(const WebPMux* mux,
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WebPChunkId id, int* num_elements);
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// Assembles all chunks in WebP RIFF format and returns in 'assembled_data'.
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// This function also validates the mux object.
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// Note: The content of 'assembled_data' will be ignored and overwritten.
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// Also, the content of 'assembled_data' is allocated using malloc(), and NOT
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// owned by the 'mux' object. It MUST be deallocated by the caller by calling
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// WebPDataClear(). It's always safe to call WebPDataClear() upon return,
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// even in case of error.
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// Parameters:
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// mux - (in/out) object whose chunks are to be assembled
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// assembled_data - (out) assembled WebP data
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// Returns:
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// WEBP_MUX_BAD_DATA - if mux object is invalid.
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// WEBP_MUX_INVALID_ARGUMENT - if mux or assembled_data is NULL.
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// WEBP_MUX_MEMORY_ERROR - on memory allocation error.
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// WEBP_MUX_OK - on success.
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WEBP_EXTERN(WebPMuxError) WebPMuxAssemble(WebPMux* mux,
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WebPData* assembled_data);
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//------------------------------------------------------------------------------
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// WebPAnimEncoder API
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//
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// This API allows encoding (possibly) animated WebP images.
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//
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// Code Example:
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/*
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WebPAnimEncoderOptions enc_options;
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WebPAnimEncoderOptionsInit(&enc_options);
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// Tune 'enc_options' as needed.
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WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
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while(<there are more frames>) {
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WebPConfig config;
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WebPConfigInit(&config);
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// Tune 'config' as needed.
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WebPAnimEncoderAdd(enc, frame, timestamp_ms, &config);
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}
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WebPAnimEncoderAdd(enc, NULL, timestamp_ms, NULL);
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WebPAnimEncoderAssemble(enc, webp_data);
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WebPAnimEncoderDelete(enc);
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// Write the 'webp_data' to a file, or re-mux it further.
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*/
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typedef struct WebPAnimEncoder WebPAnimEncoder; // Main opaque object.
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// Forward declarations. Defined in encode.h.
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struct WebPPicture;
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struct WebPConfig;
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// Global options.
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struct WebPAnimEncoderOptions {
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WebPMuxAnimParams anim_params; // Animation parameters.
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int minimize_size; // If true, minimize the output size (slow). Implicitly
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// disables key-frame insertion.
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int kmin;
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int kmax; // Minimum and maximum distance between consecutive key
|
|
// frames in the output. The library may insert some key
|
|
// frames as needed to satisfy this criteria.
|
|
// Note that these conditions should hold: kmax > kmin
|
|
// and kmin >= kmax / 2 + 1. Also, if kmax <= 0, then
|
|
// key-frame insertion is disabled; and if kmax == 1,
|
|
// then all frames will be key-frames (kmin value does
|
|
// not matter for these special cases).
|
|
int allow_mixed; // If true, use mixed compression mode; may choose
|
|
// either lossy and lossless for each frame.
|
|
int verbose; // If true, print info and warning messages to stderr.
|
|
|
|
uint32_t padding[4]; // Padding for later use.
|
|
};
|
|
|
|
// Internal, version-checked, entry point.
|
|
WEBP_EXTERN(int) WebPAnimEncoderOptionsInitInternal(
|
|
WebPAnimEncoderOptions*, int);
|
|
|
|
// Should always be called, to initialize a fresh WebPAnimEncoderOptions
|
|
// structure before modification. Returns false in case of version mismatch.
|
|
// WebPAnimEncoderOptionsInit() must have succeeded before using the
|
|
// 'enc_options' object.
|
|
static WEBP_INLINE int WebPAnimEncoderOptionsInit(
|
|
WebPAnimEncoderOptions* enc_options) {
|
|
return WebPAnimEncoderOptionsInitInternal(enc_options, WEBP_MUX_ABI_VERSION);
|
|
}
|
|
|
|
// Internal, version-checked, entry point.
|
|
WEBP_EXTERN(WebPAnimEncoder*) WebPAnimEncoderNewInternal(
|
|
int, int, const WebPAnimEncoderOptions*, int);
|
|
|
|
// Creates and initializes a WebPAnimEncoder object.
|
|
// Parameters:
|
|
// width/height - (in) canvas width and height of the animation.
|
|
// enc_options - (in) encoding options; can be passed NULL to pick
|
|
// reasonable defaults.
|
|
// Returns:
|
|
// A pointer to the newly created WebPAnimEncoder object.
|
|
// Or NULL in case of memory error.
|
|
static WEBP_INLINE WebPAnimEncoder* WebPAnimEncoderNew(
|
|
int width, int height, const WebPAnimEncoderOptions* enc_options) {
|
|
return WebPAnimEncoderNewInternal(width, height, enc_options,
|
|
WEBP_MUX_ABI_VERSION);
|
|
}
|
|
|
|
// Optimize the given frame for WebP, encode it and add it to the
|
|
// WebPAnimEncoder object.
|
|
// The last call to 'WebPAnimEncoderAdd' should be with frame = NULL, which
|
|
// indicates that no more frames are to be added. This call is also used to
|
|
// determine the duration of the last frame.
|
|
// Parameters:
|
|
// enc - (in/out) object to which the frame is to be added.
|
|
// frame - (in/out) frame data in ARGB or YUV(A) format. If it is in YUV(A)
|
|
// format, it will be converted to ARGB, which incurs a small loss.
|
|
// timestamp_ms - (in) timestamp of this frame in milliseconds.
|
|
// Duration of a frame would be calculated as
|
|
// "timestamp of next frame - timestamp of this frame".
|
|
// Hence, timestamps should be in non-decreasing order.
|
|
// config - (in) encoding options; can be passed NULL to pick
|
|
// reasonable defaults.
|
|
// Returns:
|
|
// On error, returns false and frame->error_code is set appropriately.
|
|
// Otherwise, returns true.
|
|
WEBP_EXTERN(int) WebPAnimEncoderAdd(
|
|
WebPAnimEncoder* enc, struct WebPPicture* frame, int timestamp_ms,
|
|
const struct WebPConfig* config);
|
|
|
|
// Assemble all frames added so far into a WebP bitstream.
|
|
// This call should be preceded by a call to 'WebPAnimEncoderAdd' with
|
|
// frame = NULL; if not, the duration of the last frame will be internally
|
|
// estimated.
|
|
// Parameters:
|
|
// enc - (in/out) object from which the frames are to be assembled.
|
|
// webp_data - (out) generated WebP bitstream.
|
|
// Returns:
|
|
// True on success.
|
|
WEBP_EXTERN(int) WebPAnimEncoderAssemble(WebPAnimEncoder* enc,
|
|
WebPData* webp_data);
|
|
|
|
// Get error string corresponding to the most recent call using 'enc'. The
|
|
// returned string is owned by 'enc' and is valid only until the next call to
|
|
// WebPAnimEncoderAdd() or WebPAnimEncoderAssemble() or WebPAnimEncoderDelete().
|
|
// Parameters:
|
|
// enc - (in/out) object from which the error string is to be fetched.
|
|
// Returns:
|
|
// NULL if 'enc' is NULL. Otherwise, returns the error string if the last call
|
|
// to 'enc' had an error, or an empty string if the last call was a success.
|
|
WEBP_EXTERN(const char*) WebPAnimEncoderGetError(WebPAnimEncoder* enc);
|
|
|
|
// Deletes the WebPAnimEncoder object.
|
|
// Parameters:
|
|
// enc - (in/out) object to be deleted
|
|
WEBP_EXTERN(void) WebPAnimEncoderDelete(WebPAnimEncoder* enc);
|
|
|
|
//------------------------------------------------------------------------------
|
|
|
|
#ifdef __cplusplus
|
|
} // extern "C"
|
|
#endif
|
|
|
|
#endif /* WEBP_WEBP_MUX_H_ */
|