diff CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/webp/demux.h @ 69:33d812a61356

planemo upload commit 2e9511a184a1ca667c7be0c6321a36dc4e3d116d
author jpayne
date Tue, 18 Mar 2025 17:55:14 -0400
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/CSP2/CSP2_env/env-d9b9114564458d9d-741b3de822f2aaca6c6caa4325c4afce/include/webp/demux.h	Tue Mar 18 17:55:14 2025 -0400
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+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Demux API.
+// Enables extraction of image and extended format data from WebP files.
+
+// Code Example: Demuxing WebP data to extract all the frames, ICC profile
+// and EXIF/XMP metadata.
+/*
+  WebPDemuxer* demux = WebPDemux(&webp_data);
+
+  uint32_t width = WebPDemuxGetI(demux, WEBP_FF_CANVAS_WIDTH);
+  uint32_t height = WebPDemuxGetI(demux, WEBP_FF_CANVAS_HEIGHT);
+  // ... (Get information about the features present in the WebP file).
+  uint32_t flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);
+
+  // ... (Iterate over all frames).
+  WebPIterator iter;
+  if (WebPDemuxGetFrame(demux, 1, &iter)) {
+    do {
+      // ... (Consume 'iter'; e.g. Decode 'iter.fragment' with WebPDecode(),
+      // ... and get other frame properties like width, height, offsets etc.
+      // ... see 'struct WebPIterator' below for more info).
+    } while (WebPDemuxNextFrame(&iter));
+    WebPDemuxReleaseIterator(&iter);
+  }
+
+  // ... (Extract metadata).
+  WebPChunkIterator chunk_iter;
+  if (flags & ICCP_FLAG) WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter);
+  // ... (Consume the ICC profile in 'chunk_iter.chunk').
+  WebPDemuxReleaseChunkIterator(&chunk_iter);
+  if (flags & EXIF_FLAG) WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter);
+  // ... (Consume the EXIF metadata in 'chunk_iter.chunk').
+  WebPDemuxReleaseChunkIterator(&chunk_iter);
+  if (flags & XMP_FLAG) WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter);
+  // ... (Consume the XMP metadata in 'chunk_iter.chunk').
+  WebPDemuxReleaseChunkIterator(&chunk_iter);
+  WebPDemuxDelete(demux);
+*/
+
+#ifndef WEBP_WEBP_DEMUX_H_
+#define WEBP_WEBP_DEMUX_H_
+
+#include "./decode.h"     // for WEBP_CSP_MODE
+#include "./mux_types.h"
+#include "./types.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#define WEBP_DEMUX_ABI_VERSION 0x0107    // MAJOR(8b) + MINOR(8b)
+
+// Note: forward declaring enumerations is not allowed in (strict) C and C++,
+// the types are left here for reference.
+// typedef enum WebPDemuxState WebPDemuxState;
+// typedef enum WebPFormatFeature WebPFormatFeature;
+typedef struct WebPDemuxer WebPDemuxer;
+typedef struct WebPIterator WebPIterator;
+typedef struct WebPChunkIterator WebPChunkIterator;
+typedef struct WebPAnimInfo WebPAnimInfo;
+typedef struct WebPAnimDecoderOptions WebPAnimDecoderOptions;
+
+//------------------------------------------------------------------------------
+
+// Returns the version number of the demux library, packed in hexadecimal using
+// 8bits for each of major/minor/revision. E.g: v2.5.7 is 0x020507.
+WEBP_EXTERN int WebPGetDemuxVersion(void);
+
+//------------------------------------------------------------------------------
+// Life of a Demux object
+
+typedef enum WebPDemuxState {
+  WEBP_DEMUX_PARSE_ERROR    = -1,  // An error occurred while parsing.
+  WEBP_DEMUX_PARSING_HEADER =  0,  // Not enough data to parse full header.
+  WEBP_DEMUX_PARSED_HEADER  =  1,  // Header parsing complete,
+                                   // data may be available.
+  WEBP_DEMUX_DONE           =  2   // Entire file has been parsed.
+} WebPDemuxState;
+
+// Internal, version-checked, entry point
+WEBP_NODISCARD WEBP_EXTERN WebPDemuxer* WebPDemuxInternal(
+    const WebPData*, int, WebPDemuxState*, int);
+
+// Parses the full WebP file given by 'data'. For single images the WebP file
+// header alone or the file header and the chunk header may be absent.
+// Returns a WebPDemuxer object on successful parse, NULL otherwise.
+WEBP_NODISCARD static WEBP_INLINE WebPDemuxer* WebPDemux(const WebPData* data) {
+  return WebPDemuxInternal(data, 0, NULL, WEBP_DEMUX_ABI_VERSION);
+}
+
+// Parses the possibly incomplete WebP file given by 'data'.
+// If 'state' is non-NULL it will be set to indicate the status of the demuxer.
+// Returns NULL in case of error or if there isn't enough data to start parsing;
+// and a WebPDemuxer object on successful parse.
+// Note that WebPDemuxer keeps internal pointers to 'data' memory segment.
+// If this data is volatile, the demuxer object should be deleted (by calling
+// WebPDemuxDelete()) and WebPDemuxPartial() called again on the new data.
+// This is usually an inexpensive operation.
+WEBP_NODISCARD static WEBP_INLINE WebPDemuxer* WebPDemuxPartial(
+    const WebPData* data, WebPDemuxState* state) {
+  return WebPDemuxInternal(data, 1, state, WEBP_DEMUX_ABI_VERSION);
+}
+
+// Frees memory associated with 'dmux'.
+WEBP_EXTERN void WebPDemuxDelete(WebPDemuxer* dmux);
+
+//------------------------------------------------------------------------------
+// Data/information extraction.
+
+typedef enum WebPFormatFeature {
+  WEBP_FF_FORMAT_FLAGS,      // bit-wise combination of WebPFeatureFlags
+                             // corresponding to the 'VP8X' chunk (if present).
+  WEBP_FF_CANVAS_WIDTH,
+  WEBP_FF_CANVAS_HEIGHT,
+  WEBP_FF_LOOP_COUNT,        // only relevant for animated file
+  WEBP_FF_BACKGROUND_COLOR,  // idem.
+  WEBP_FF_FRAME_COUNT        // Number of frames present in the demux object.
+                             // In case of a partial demux, this is the number
+                             // of frames seen so far, with the last frame
+                             // possibly being partial.
+} WebPFormatFeature;
+
+// Get the 'feature' value from the 'dmux'.
+// NOTE: values are only valid if WebPDemux() was used or WebPDemuxPartial()
+// returned a state > WEBP_DEMUX_PARSING_HEADER.
+// If 'feature' is WEBP_FF_FORMAT_FLAGS, the returned value is a bit-wise
+// combination of WebPFeatureFlags values.
+// If 'feature' is WEBP_FF_LOOP_COUNT, WEBP_FF_BACKGROUND_COLOR, the returned
+// value is only meaningful if the bitstream is animated.
+WEBP_EXTERN uint32_t WebPDemuxGetI(
+    const WebPDemuxer* dmux, WebPFormatFeature feature);
+
+//------------------------------------------------------------------------------
+// Frame iteration.
+
+struct WebPIterator {
+  int frame_num;
+  int num_frames;          // equivalent to WEBP_FF_FRAME_COUNT.
+  int x_offset, y_offset;  // offset relative to the canvas.
+  int width, height;       // dimensions of this frame.
+  int duration;            // display duration in milliseconds.
+  WebPMuxAnimDispose dispose_method;  // dispose method for the frame.
+  int complete;   // true if 'fragment' contains a full frame. partial images
+                  // may still be decoded with the WebP incremental decoder.
+  WebPData fragment;  // The frame given by 'frame_num'. Note for historical
+                      // reasons this is called a fragment.
+  int has_alpha;      // True if the frame contains transparency.
+  WebPMuxAnimBlend blend_method;  // Blend operation for the frame.
+
+  uint32_t pad[2];         // padding for later use.
+  void* private_;          // for internal use only.
+};
+
+// Retrieves frame 'frame_number' from 'dmux'.
+// 'iter->fragment' points to the frame on return from this function.
+// Setting 'frame_number' equal to 0 will return the last frame of the image.
+// Returns false if 'dmux' is NULL or frame 'frame_number' is not present.
+// Call WebPDemuxReleaseIterator() when use of the iterator is complete.
+// NOTE: 'dmux' must persist for the lifetime of 'iter'.
+WEBP_NODISCARD WEBP_EXTERN int WebPDemuxGetFrame(
+    const WebPDemuxer* dmux, int frame_number, WebPIterator* iter);
+
+// Sets 'iter->fragment' to point to the next ('iter->frame_num' + 1) or
+// previous ('iter->frame_num' - 1) frame. These functions do not loop.
+// Returns true on success, false otherwise.
+WEBP_NODISCARD WEBP_EXTERN int WebPDemuxNextFrame(WebPIterator* iter);
+WEBP_NODISCARD WEBP_EXTERN int WebPDemuxPrevFrame(WebPIterator* iter);
+
+// Releases any memory associated with 'iter'.
+// Must be called before any subsequent calls to WebPDemuxGetChunk() on the same
+// iter. Also, must be called before destroying the associated WebPDemuxer with
+// WebPDemuxDelete().
+WEBP_EXTERN void WebPDemuxReleaseIterator(WebPIterator* iter);
+
+//------------------------------------------------------------------------------
+// Chunk iteration.
+
+struct WebPChunkIterator {
+  // The current and total number of chunks with the fourcc given to
+  // WebPDemuxGetChunk().
+  int chunk_num;
+  int num_chunks;
+  WebPData chunk;    // The payload of the chunk.
+
+  uint32_t pad[6];   // padding for later use
+  void* private_;
+};
+
+// Retrieves the 'chunk_number' instance of the chunk with id 'fourcc' from
+// 'dmux'.
+// 'fourcc' is a character array containing the fourcc of the chunk to return,
+// e.g., "ICCP", "XMP ", "EXIF", etc.
+// Setting 'chunk_number' equal to 0 will return the last chunk in a set.
+// Returns true if the chunk is found, false otherwise. Image related chunk
+// payloads are accessed through WebPDemuxGetFrame() and related functions.
+// Call WebPDemuxReleaseChunkIterator() when use of the iterator is complete.
+// NOTE: 'dmux' must persist for the lifetime of the iterator.
+WEBP_NODISCARD WEBP_EXTERN int WebPDemuxGetChunk(const WebPDemuxer* dmux,
+                                                 const char fourcc[4],
+                                                 int chunk_number,
+                                                 WebPChunkIterator* iter);
+
+// Sets 'iter->chunk' to point to the next ('iter->chunk_num' + 1) or previous
+// ('iter->chunk_num' - 1) chunk. These functions do not loop.
+// Returns true on success, false otherwise.
+WEBP_NODISCARD WEBP_EXTERN int WebPDemuxNextChunk(WebPChunkIterator* iter);
+WEBP_NODISCARD WEBP_EXTERN int WebPDemuxPrevChunk(WebPChunkIterator* iter);
+
+// Releases any memory associated with 'iter'.
+// Must be called before destroying the associated WebPDemuxer with
+// WebPDemuxDelete().
+WEBP_EXTERN void WebPDemuxReleaseChunkIterator(WebPChunkIterator* iter);
+
+//------------------------------------------------------------------------------
+// WebPAnimDecoder API
+//
+// This API allows decoding (possibly) animated WebP images.
+//
+// Code Example:
+/*
+  WebPAnimDecoderOptions dec_options;
+  WebPAnimDecoderOptionsInit(&dec_options);
+  // Tune 'dec_options' as needed.
+  WebPAnimDecoder* dec = WebPAnimDecoderNew(webp_data, &dec_options);
+  WebPAnimInfo anim_info;
+  WebPAnimDecoderGetInfo(dec, &anim_info);
+  for (uint32_t i = 0; i < anim_info.loop_count; ++i) {
+    while (WebPAnimDecoderHasMoreFrames(dec)) {
+      uint8_t* buf;
+      int timestamp;
+      WebPAnimDecoderGetNext(dec, &buf, &timestamp);
+      // ... (Render 'buf' based on 'timestamp').
+      // ... (Do NOT free 'buf', as it is owned by 'dec').
+    }
+    WebPAnimDecoderReset(dec);
+  }
+  const WebPDemuxer* demuxer = WebPAnimDecoderGetDemuxer(dec);
+  // ... (Do something using 'demuxer'; e.g. get EXIF/XMP/ICC data).
+  WebPAnimDecoderDelete(dec);
+*/
+
+typedef struct WebPAnimDecoder WebPAnimDecoder;  // Main opaque object.
+
+// Global options.
+struct WebPAnimDecoderOptions {
+  // Output colorspace. Only the following modes are supported:
+  // MODE_RGBA, MODE_BGRA, MODE_rgbA and MODE_bgrA.
+  WEBP_CSP_MODE color_mode;
+  int use_threads;           // If true, use multi-threaded decoding.
+  uint32_t padding[7];       // Padding for later use.
+};
+
+// Internal, version-checked, entry point.
+WEBP_NODISCARD WEBP_EXTERN int WebPAnimDecoderOptionsInitInternal(
+    WebPAnimDecoderOptions*, int);
+
+// Should always be called, to initialize a fresh WebPAnimDecoderOptions
+// structure before modification. Returns false in case of version mismatch.
+// WebPAnimDecoderOptionsInit() must have succeeded before using the
+// 'dec_options' object.
+WEBP_NODISCARD static WEBP_INLINE int WebPAnimDecoderOptionsInit(
+    WebPAnimDecoderOptions* dec_options) {
+  return WebPAnimDecoderOptionsInitInternal(dec_options,
+                                            WEBP_DEMUX_ABI_VERSION);
+}
+
+// Internal, version-checked, entry point.
+WEBP_NODISCARD WEBP_EXTERN WebPAnimDecoder* WebPAnimDecoderNewInternal(
+    const WebPData*, const WebPAnimDecoderOptions*, int);
+
+// Creates and initializes a WebPAnimDecoder object.
+// Parameters:
+//   webp_data - (in) WebP bitstream. This should remain unchanged during the
+//                    lifetime of the output WebPAnimDecoder object.
+//   dec_options - (in) decoding options. Can be passed NULL to choose
+//                      reasonable defaults (in particular, color mode MODE_RGBA
+//                      will be picked).
+// Returns:
+//   A pointer to the newly created WebPAnimDecoder object, or NULL in case of
+//   parsing error, invalid option or memory error.
+WEBP_NODISCARD static WEBP_INLINE WebPAnimDecoder* WebPAnimDecoderNew(
+    const WebPData* webp_data, const WebPAnimDecoderOptions* dec_options) {
+  return WebPAnimDecoderNewInternal(webp_data, dec_options,
+                                    WEBP_DEMUX_ABI_VERSION);
+}
+
+// Global information about the animation..
+struct WebPAnimInfo {
+  uint32_t canvas_width;
+  uint32_t canvas_height;
+  uint32_t loop_count;
+  uint32_t bgcolor;
+  uint32_t frame_count;
+  uint32_t pad[4];   // padding for later use
+};
+
+// Get global information about the animation.
+// Parameters:
+//   dec - (in) decoder instance to get information from.
+//   info - (out) global information fetched from the animation.
+// Returns:
+//   True on success.
+WEBP_NODISCARD WEBP_EXTERN int WebPAnimDecoderGetInfo(
+    const WebPAnimDecoder* dec, WebPAnimInfo* info);
+
+// Fetch the next frame from 'dec' based on options supplied to
+// WebPAnimDecoderNew(). This will be a fully reconstructed canvas of size
+// 'canvas_width * 4 * canvas_height', and not just the frame sub-rectangle. The
+// returned buffer 'buf' is valid only until the next call to
+// WebPAnimDecoderGetNext(), WebPAnimDecoderReset() or WebPAnimDecoderDelete().
+// Parameters:
+//   dec - (in/out) decoder instance from which the next frame is to be fetched.
+//   buf - (out) decoded frame.
+//   timestamp - (out) timestamp of the frame in milliseconds.
+// Returns:
+//   False if any of the arguments are NULL, or if there is a parsing or
+//   decoding error, or if there are no more frames. Otherwise, returns true.
+WEBP_NODISCARD WEBP_EXTERN int WebPAnimDecoderGetNext(WebPAnimDecoder* dec,
+                                                      uint8_t** buf,
+                                                      int* timestamp);
+
+// Check if there are more frames left to decode.
+// Parameters:
+//   dec - (in) decoder instance to be checked.
+// Returns:
+//   True if 'dec' is not NULL and some frames are yet to be decoded.
+//   Otherwise, returns false.
+WEBP_NODISCARD WEBP_EXTERN int WebPAnimDecoderHasMoreFrames(
+    const WebPAnimDecoder* dec);
+
+// Resets the WebPAnimDecoder object, so that next call to
+// WebPAnimDecoderGetNext() will restart decoding from 1st frame. This would be
+// helpful when all frames need to be decoded multiple times (e.g.
+// info.loop_count times) without destroying and recreating the 'dec' object.
+// Parameters:
+//   dec - (in/out) decoder instance to be reset
+WEBP_EXTERN void WebPAnimDecoderReset(WebPAnimDecoder* dec);
+
+// Grab the internal demuxer object.
+// Getting the demuxer object can be useful if one wants to use operations only
+// available through demuxer; e.g. to get XMP/EXIF/ICC metadata. The returned
+// demuxer object is owned by 'dec' and is valid only until the next call to
+// WebPAnimDecoderDelete().
+//
+// Parameters:
+//   dec - (in) decoder instance from which the demuxer object is to be fetched.
+WEBP_NODISCARD WEBP_EXTERN const WebPDemuxer* WebPAnimDecoderGetDemuxer(
+    const WebPAnimDecoder* dec);
+
+// Deletes the WebPAnimDecoder object.
+// Parameters:
+//   dec - (in/out) decoder instance to be deleted
+WEBP_EXTERN void WebPAnimDecoderDelete(WebPAnimDecoder* dec);
+
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
+#endif  // WEBP_WEBP_DEMUX_H_