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Mux API:
========
The Mux API contains methods for adding data to and reading data from WebP
files. This API currently supports XMP/EXIF metadata, ICC profile and animation.
Other features may be added in subsequent releases.

Example#1 (pseudo code): Creating a WebPMux object with image data, color
profile and XMP metadata.

  int copy_data = 0;
  WebPMux* mux = WebPMuxNew();
  // ... (Prepare image data).
  WebPMuxSetImage(mux, &image, copy_data);
  // ... (Prepare ICC profile data).
  WebPMuxSetChunk(mux, "ICCP", &icc_profile, copy_data);
  // ... (Prepare XMP metadata).
  WebPMuxSetChunk(mux, "XMP ", &xmp, copy_data);
  // Get data from mux in WebP RIFF format.
  WebPMuxAssemble(mux, &output_data);
  WebPMuxDelete(mux);
  // ... (Consume output_data; e.g. write output_data.bytes to file).
  WebPDataClear(&output_data);


Example#2 (pseudo code): Get image and color profile data from a WebP file.

  int copy_data = 0;
  // ... (Read data from file).
  WebPMux* mux = WebPMuxCreate(&data, copy_data);
  WebPMuxGetFrame(mux, 1, &image);
  // ... (Consume image; e.g. call WebPDecode() to decode the data).
  WebPMuxGetChunk(mux, "ICCP", &icc_profile);
  // ... (Consume icc_profile).
  WebPMuxDelete(mux);
  free(data);


For a detailed Mux API reference, please refer to the header file
(src/webp/mux.h).

Demux API:
==========
The Demux API enables extraction of images and extended format data from
WebP files. This API currently supports reading of XMP/EXIF metadata, ICC
profile and animated images. Other features may be added in subsequent
releases.

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);


For a detailed Demux API reference, please refer to the header file
(src/webp/demux.h).

AnimEncoder API:
================
The AnimEncoder API can be used to create animated WebP images.

Code example:

  WebPAnimEncoderOptions enc_options;
  WebPAnimEncoderOptionsInit(&enc_options);
  // ... (Tune 'enc_options' as needed).
  WebPAnimEncoder* enc = WebPAnimEncoderNew(width, height, &enc_options);
  while(<there are more frames>) {
    WebPConfig config;
    WebPConfigInit(&config);
    // ... (Tune 'config' as needed).
    WebPAnimEncoderAdd(enc, frame, duration, &config);
  }
  WebPAnimEncoderAssemble(enc, webp_data);
  WebPAnimEncoderDelete(enc);
  // ... (Write the 'webp_data' to a file, or re-mux it further).


For a detailed AnimEncoder API reference, please refer to the header file
(src/webp/mux.h).


Bugs:
=====

Please report all bugs to our issue tracker:
    http://code.google.com/p/webp/issues
Patches welcome! See this page to get started:
    http://www.webmproject.org/code/contribute/submitting-patches/

Discuss:
========

Email: webp-discuss@webmproject.org