Coverage Report

Created: 2025-06-16 07:00

/work/include/webp/mux.h
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// 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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#include "./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 0x0109        // 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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  WebPFree(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 WEBP_NODISCARD 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_NODISCARD 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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0
WEBP_NODISCARD static WEBP_INLINE WebPMux* WebPMuxNew(void) {
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0
  return WebPNewInternal(WEBP_MUX_ABI_VERSION);
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0
}
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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_NODISCARD WEBP_EXTERN WebPMux* WebPMuxCreateInternal(const WebPData*, int,
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                                                          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. If the
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//               data is not copied, it must exist for the lifetime of the
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//               mux object.
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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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WEBP_NODISCARD static WEBP_INLINE WebPMux* WebPMuxCreate(
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    const WebPData* bitstream, 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. If the
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//               data is not copied, it must exist until a call to
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//               WebPMuxAssemble() is made.
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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. If the
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//               data is not copied, it must exist until a call to
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//               WebPMuxAssemble() is made.
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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. If the
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//               data is not copied, it must exist until a call to
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//               WebPMuxAssemble() is made.
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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(
255
    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 WebPMalloc(), 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(
273
    const WebPMux* mux, uint32_t nth, WebPMuxFrameInfo* frame);
274
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// Deletes a frame from the mux object.
276
// nth=0 has a special meaning - last position.
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// Parameters:
278
//   mux - (in/out) object from which a frame is to be deleted
279
//   nth - (in) The position from which the frame is to be deleted
280
// Returns:
281
//   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
283
//                        before deletion.
284
//   WEBP_MUX_OK - on success.
285
WEBP_EXTERN WebPMuxError WebPMuxDeleteFrame(WebPMux* mux, uint32_t nth);
286
287
//------------------------------------------------------------------------------
288
// Animation.
289
290
// Animation parameters.
291
struct WebPMuxAnimParams {
292
  uint32_t bgcolor;  // Background color of the canvas stored (in MSB order) as:
293
                     // Bits 00 to 07: Alpha.
294
                     // Bits 08 to 15: Red.
295
                     // Bits 16 to 23: Green.
296
                     // Bits 24 to 31: Blue.
297
  int loop_count;    // Number of times to repeat the animation [0 = infinite].
298
};
299
300
// Sets the animation parameters in the mux object. Any existing ANIM chunks
301
// will be removed.
302
// Parameters:
303
//   mux - (in/out) object in which ANIM chunk is to be set/added
304
//   params - (in) animation parameters.
305
// Returns:
306
//   WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
307
//   WEBP_MUX_MEMORY_ERROR - on memory allocation error.
308
//   WEBP_MUX_OK - on success.
309
WEBP_EXTERN WebPMuxError WebPMuxSetAnimationParams(
310
    WebPMux* mux, const WebPMuxAnimParams* params);
311
312
// Gets the animation parameters from the mux object.
313
// Parameters:
314
//   mux - (in) object from which the animation parameters to be fetched
315
//   params - (out) animation parameters extracted from the ANIM chunk
316
// Returns:
317
//   WEBP_MUX_INVALID_ARGUMENT - if mux or params is NULL.
318
//   WEBP_MUX_NOT_FOUND - if ANIM chunk is not present in mux object.
319
//   WEBP_MUX_OK - on success.
320
WEBP_EXTERN WebPMuxError WebPMuxGetAnimationParams(
321
    const WebPMux* mux, WebPMuxAnimParams* params);
322
323
//------------------------------------------------------------------------------
324
// Misc Utilities.
325
326
// Sets the canvas size for the mux object. The width and height can be
327
// specified explicitly or left as zero (0, 0).
328
// * When width and height are specified explicitly, then this frame bound is
329
//   enforced during subsequent calls to WebPMuxAssemble() and an error is
330
//   reported if any animated frame does not completely fit within the canvas.
331
// * When unspecified (0, 0), the constructed canvas will get the frame bounds
332
//   from the bounding-box over all frames after calling WebPMuxAssemble().
333
// Parameters:
334
//   mux - (in) object to which the canvas size is to be set
335
//   width - (in) canvas width
336
//   height - (in) canvas height
337
// Returns:
338
//   WEBP_MUX_INVALID_ARGUMENT - if mux is NULL; or
339
//                               width or height are invalid or out of bounds
340
//   WEBP_MUX_OK - on success.
341
WEBP_EXTERN WebPMuxError WebPMuxSetCanvasSize(WebPMux* mux,
342
                                              int width, int height);
343
344
// Gets the canvas size from the mux object.
345
// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
346
// That is, the mux object hasn't been modified since the last call to
347
// WebPMuxAssemble() or WebPMuxCreate().
348
// Parameters:
349
//   mux - (in) object from which the canvas size is to be fetched
350
//   width - (out) canvas width
351
//   height - (out) canvas height
352
// Returns:
353
//   WEBP_MUX_INVALID_ARGUMENT - if mux, width or height is NULL.
354
//   WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
355
//   WEBP_MUX_OK - on success.
356
WEBP_EXTERN WebPMuxError WebPMuxGetCanvasSize(const WebPMux* mux,
357
                                              int* width, int* height);
358
359
// Gets the feature flags from the mux object.
360
// Note: This method assumes that the VP8X chunk, if present, is up-to-date.
361
// That is, the mux object hasn't been modified since the last call to
362
// WebPMuxAssemble() or WebPMuxCreate().
363
// Parameters:
364
//   mux - (in) object from which the features are to be fetched
365
//   flags - (out) the flags specifying which features are present in the
366
//           mux object. This will be an OR of various flag values.
367
//           Enum 'WebPFeatureFlags' can be used to test individual flag values.
368
// Returns:
369
//   WEBP_MUX_INVALID_ARGUMENT - if mux or flags is NULL.
370
//   WEBP_MUX_BAD_DATA - if VP8X/VP8/VP8L chunk or canvas size is invalid.
371
//   WEBP_MUX_OK - on success.
372
WEBP_EXTERN WebPMuxError WebPMuxGetFeatures(const WebPMux* mux,
373
                                            uint32_t* flags);
374
375
// Gets number of chunks with the given 'id' in the mux object.
376
// Parameters:
377
//   mux - (in) object from which the info is to be fetched
378
//   id - (in) chunk id specifying the type of chunk
379
//   num_elements - (out) number of chunks with the given chunk id
380
// Returns:
381
//   WEBP_MUX_INVALID_ARGUMENT - if mux, or num_elements is NULL.
382
//   WEBP_MUX_OK - on success.
383
WEBP_EXTERN WebPMuxError WebPMuxNumChunks(const WebPMux* mux,
384
                                          WebPChunkId id, int* num_elements);
385
386
// Assembles all chunks in WebP RIFF format and returns in 'assembled_data'.
387
// This function also validates the mux object.
388
// Note: The content of 'assembled_data' will be ignored and overwritten.
389
// Also, the content of 'assembled_data' is allocated using WebPMalloc(), and
390
// NOT owned by the 'mux' object. It MUST be deallocated by the caller by
391
// calling WebPDataClear(). It's always safe to call WebPDataClear() upon
392
// return, even in case of error.
393
// Parameters:
394
//   mux - (in/out) object whose chunks are to be assembled
395
//   assembled_data - (out) assembled WebP data
396
// Returns:
397
//   WEBP_MUX_BAD_DATA - if mux object is invalid.
398
//   WEBP_MUX_INVALID_ARGUMENT - if mux or assembled_data is NULL.
399
//   WEBP_MUX_MEMORY_ERROR - on memory allocation error.
400
//   WEBP_MUX_OK - on success.
401
WEBP_EXTERN WebPMuxError WebPMuxAssemble(WebPMux* mux,
402
                                         WebPData* assembled_data);
403
404
//------------------------------------------------------------------------------
405
// WebPAnimEncoder API
406
//
407
// This API allows encoding (possibly) animated WebP images.
408
//
409
// Code Example:
410
/*
411
  WebPAnimEncoderOptions enc_options;
412
  WebPAnimEncoderOptionsInit(&enc_options);
413
  // Tune 'enc_options' as needed.
414
  WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
415
  while(<there are more frames>) {
416
    WebPConfig config;
417
    WebPConfigInit(&config);
418
    // Tune 'config' as needed.
419
    WebPAnimEncoderAdd(enc, frame, timestamp_ms, &config);
420
  }
421
  WebPAnimEncoderAdd(enc, NULL, timestamp_ms, NULL);
422
  WebPAnimEncoderAssemble(enc, webp_data);
423
  WebPAnimEncoderDelete(enc);
424
  // Write the 'webp_data' to a file, or re-mux it further.
425
*/
426
427
typedef struct WebPAnimEncoder WebPAnimEncoder;  // Main opaque object.
428
429
// Forward declarations. Defined in encode.h.
430
struct WebPPicture;
431
struct WebPConfig;
432
433
// Global options.
434
struct WebPAnimEncoderOptions {
435
  WebPMuxAnimParams anim_params;  // Animation parameters.
436
  int minimize_size;    // If true, minimize the output size (slow). Implicitly
437
                        // disables key-frame insertion.
438
  int kmin;
439
  int kmax;             // Minimum and maximum distance between consecutive key
440
                        // frames in the output. The library may insert some key
441
                        // frames as needed to satisfy this criteria.
442
                        // Note that these conditions should hold: kmax > kmin
443
                        // and kmin >= kmax / 2 + 1. Also, if kmax <= 0, then
444
                        // key-frame insertion is disabled; and if kmax == 1,
445
                        // then all frames will be key-frames (kmin value does
446
                        // not matter for these special cases).
447
  int allow_mixed;      // If true, use mixed compression mode; may choose
448
                        // either lossy and lossless for each frame.
449
  int verbose;          // If true, print info and warning messages to stderr.
450
451
  uint32_t padding[4];  // Padding for later use.
452
};
453
454
// Internal, version-checked, entry point.
455
WEBP_EXTERN int WebPAnimEncoderOptionsInitInternal(
456
    WebPAnimEncoderOptions*, int);
457
458
// Should always be called, to initialize a fresh WebPAnimEncoderOptions
459
// structure before modification. Returns false in case of version mismatch.
460
// WebPAnimEncoderOptionsInit() must have succeeded before using the
461
// 'enc_options' object.
462
WEBP_NODISCARD static WEBP_INLINE int WebPAnimEncoderOptionsInit(
463
0
    WebPAnimEncoderOptions* enc_options) {
464
0
  return WebPAnimEncoderOptionsInitInternal(enc_options, WEBP_MUX_ABI_VERSION);
465
0
}
466
467
// Internal, version-checked, entry point.
468
WEBP_EXTERN WebPAnimEncoder* WebPAnimEncoderNewInternal(
469
    int, int, const WebPAnimEncoderOptions*, int);
470
471
// Creates and initializes a WebPAnimEncoder object.
472
// Parameters:
473
//   width/height - (in) canvas width and height of the animation.
474
//   enc_options - (in) encoding options; can be passed NULL to pick
475
//                      reasonable defaults.
476
// Returns:
477
//   A pointer to the newly created WebPAnimEncoder object.
478
//   Or NULL in case of memory error.
479
static WEBP_INLINE WebPAnimEncoder* WebPAnimEncoderNew(
480
0
    int width, int height, const WebPAnimEncoderOptions* enc_options) {
481
0
  return WebPAnimEncoderNewInternal(width, height, enc_options,
482
0
                                    WEBP_MUX_ABI_VERSION);
483
0
}
484
485
// Optimize the given frame for WebP, encode it and add it to the
486
// WebPAnimEncoder object.
487
// The last call to 'WebPAnimEncoderAdd' should be with frame = NULL, which
488
// indicates that no more frames are to be added. This call is also used to
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// determine the duration of the last frame.
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// Parameters:
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//   enc - (in/out) object to which the frame is to be added.
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//   frame - (in/out) frame data in ARGB or YUV(A) format. If it is in YUV(A)
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//           format, it will be converted to ARGB, which incurs a small loss.
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//   timestamp_ms - (in) timestamp of this frame in milliseconds.
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//                       Duration of a frame would be calculated as
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//                       "timestamp of next frame - timestamp of this frame".
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//                       Hence, timestamps should be in non-decreasing order.
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//   config - (in) encoding options; can be passed NULL to pick
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//            reasonable defaults.
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// Returns:
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//   On error, returns false and frame->error_code is set appropriately.
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//   Otherwise, returns true.
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WEBP_NODISCARD WEBP_EXTERN int WebPAnimEncoderAdd(
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    WebPAnimEncoder* enc, struct WebPPicture* frame, int timestamp_ms,
505
    const struct WebPConfig* config);
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// Assemble all frames added so far into a WebP bitstream.
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// This call should be preceded by  a call to 'WebPAnimEncoderAdd' with
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// frame = NULL; if not, the duration of the last frame will be internally
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// estimated.
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// Parameters:
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//   enc - (in/out) object from which the frames are to be assembled.
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//   webp_data - (out) generated WebP bitstream.
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// Returns:
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//   True on success.
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WEBP_NODISCARD WEBP_EXTERN int WebPAnimEncoderAssemble(WebPAnimEncoder* enc,
517
                                                       WebPData* webp_data);
518
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// Get error string corresponding to the most recent call using 'enc'. The
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// returned string is owned by 'enc' and is valid only until the next call to
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// WebPAnimEncoderAdd() or WebPAnimEncoderAssemble() or WebPAnimEncoderDelete().
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// Parameters:
523
//   enc - (in/out) object from which the error string is to be fetched.
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// Returns:
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//   NULL if 'enc' is NULL. Otherwise, returns the error string if the last call
526
//   to 'enc' had an error, or an empty string if the last call was a success.
527
WEBP_EXTERN const char* WebPAnimEncoderGetError(WebPAnimEncoder* enc);
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529
// Deletes the WebPAnimEncoder object.
530
// Parameters:
531
//   enc - (in/out) object to be deleted
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WEBP_EXTERN void WebPAnimEncoderDelete(WebPAnimEncoder* enc);
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534
//------------------------------------------------------------------------------
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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").
539
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// Adds a chunk with id 'fourcc' and data 'chunk_data' in the enc object.
541
// Any existing chunk(s) with the same id will be removed.
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// Parameters:
543
//   enc - (in/out) object to which the chunk is to be added
544
//   fourcc - (in) a character array containing the fourcc of the given chunk;
545
//                 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 enc
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//               object and value 0 indicates data will NOT be copied. If the
549
//               data is not copied, it must exist until a call to
550
//               WebPAnimEncoderAssemble() is made.
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// Returns:
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//   WEBP_MUX_INVALID_ARGUMENT - if enc, fourcc or chunk_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 WebPAnimEncoderSetChunk(
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    WebPAnimEncoder* enc, const char fourcc[4], const WebPData* chunk_data,
557
    int copy_data);
558
559
// Gets a reference to the data of the chunk with id 'fourcc' in the enc object.
560
// The caller should NOT free the returned data.
561
// Parameters:
562
//   enc - (in) object from which the chunk data is to be fetched
563
//   fourcc - (in) a character array containing the fourcc of the chunk;
564
//                 e.g., "ICCP", "XMP ", "EXIF", etc.
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//   chunk_data - (out) returned chunk data
566
// Returns:
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//   WEBP_MUX_INVALID_ARGUMENT - if enc, fourcc or chunk_data is NULL.
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//   WEBP_MUX_NOT_FOUND - If enc does not contain a chunk with the given id.
569
//   WEBP_MUX_OK - on success.
570
WEBP_EXTERN WebPMuxError WebPAnimEncoderGetChunk(
571
    const WebPAnimEncoder* enc, const char fourcc[4], WebPData* chunk_data);
572
573
// Deletes the chunk with the given 'fourcc' from the enc object.
574
// Parameters:
575
//   enc - (in/out) object from which the chunk is to be deleted
576
//   fourcc - (in) a character array containing the fourcc of the chunk;
577
//                 e.g., "ICCP", "XMP ", "EXIF", etc.
578
// Returns:
579
//   WEBP_MUX_INVALID_ARGUMENT - if enc or fourcc is NULL.
580
//   WEBP_MUX_NOT_FOUND - If enc does not contain a chunk with the given fourcc.
581
//   WEBP_MUX_OK - on success.
582
WEBP_EXTERN WebPMuxError WebPAnimEncoderDeleteChunk(
583
    WebPAnimEncoder* enc, const char fourcc[4]);
584
585
//------------------------------------------------------------------------------
586
587
#ifdef __cplusplus
588
}    // extern "C"
589
#endif
590
591
#endif  // WEBP_WEBP_MUX_H_