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119 lines
3.7 KiB
Plaintext
119 lines
3.7 KiB
Plaintext
__ __ ____ ____ ____ __ __ _ __ __
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/ \\/ \/ _ \/ _ \/ _ \/ \ \/ \___/_ / _\
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\ / __/ _ \ __/ / / (_/ /__
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\__\__/\_____/_____/__/ \__//_/\_____/__/___/
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Description:
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============
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WebP Mux: library to create a WebP container object for features like
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color profile, XMP metadata, animation & tiling. A reference command line
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tool 'webpmux' and WebP container specification 'doc/webp-container-spec.txt'
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are also provided in this package.
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WebP Mux tool:
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==============
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The examples/ directory contains a tool (webpmux) for manipulating WebP
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files. The webpmux tool can be used to create a WebP container file and to
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extract or strip relevant data from the container file.
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A list of options is available using the -help command line flag:
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> webpmux -help
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Usage: webpmux -get GET_OPTIONS INPUT -o OUTPUT
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webpmux -set SET_OPTIONS INPUT -o OUTPUT
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webpmux -strip STRIP_OPTIONS INPUT -o OUTPUT
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webpmux -tile TILE_OPTIONS [-tile...] -o OUTPUT
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webpmux -frame FRAME_OPTIONS [-frame...] -loop LOOP_COUNT -o OUTPUT
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webpmux -info INPUT
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webpmux [-h|-help]
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GET_OPTIONS:
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Extract relevant data.
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icc Get ICCP Color profile.
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xmp Get XMP metadata.
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tile n Get nth tile.
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frame n Get nth frame.
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SET_OPTIONS:
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Set color profile/metadata.
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icc Set ICC Color profile.
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xmp Set XMP metadata.
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STRIP_OPTIONS:
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Strip color profile/metadata.
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icc Strip ICCP color profile.
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xmp Strip XMP metadata.
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TILE_OPTIONS(i):
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Create tiled image.
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file_i +xi+yi
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where: 'file_i' is the i'th tile (webp format),
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'xi','yi' specify the image offset for this tile.
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FRAME_OPTIONS(i):
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Create animation.
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file_i +xi+yi+di
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where: 'file_i' is the i'th animation frame (webp format),
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'xi','yi' specify the image offset for this frame.
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'di' is the pause duration before next frame.
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INPUT & OUTPUT are in webp format.
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WebP Mux API:
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==============
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The WebP Mux API contains methods for adding data to and reading data from
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WebPMux (a WebP container object). This API currently supports XMP metadata,
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color profile, animation & tiling. Other features will be added in subsequent
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releases.
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Example#1 (pseudo code): Creating a WebPMux object with image data, color
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profile & XMP metadata.
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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_data, image_data_size, alpha_data, alpha_size,
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copy_data);
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// ... (Prepare ICCP color profile data).
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WebPMuxSetColorProfile(mux, icc_data, icc_data_size, copy_data);
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// ... (Prepare XMP metadata).
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WebPMuxSetMetadata(mux, xmp_data, xmp_data_size, copy_data);
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// Get data from mux in WebP RIFF format.
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WebPMuxAssemble(mux, &output_data, &output_data_size);
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WebPMuxDelete(mux);
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// ... (Consume output_data; e.g. write output_data to file).
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free(output_data);
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Example#2 (pseudo code): Get image & color profile data from a WebP file.
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int copy_data = 0;
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// ... (Read data from file).
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WebPMux* mux = WebPMuxCreate(data, data_size, copy_data);
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WebPMuxGetImage(mux, &image, &alpha);
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// ... (Consume image; e.g. call WebPDecode() to decode the data).
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WebPMuxGetColorProfile(mux, &icc_chunkdata);
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// ... (Consume icc_chunkdata).
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WebPMuxDelete(mux);
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free(data);
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For detailed Mux API reference, please refer to the header file (src/webp/mux.h)
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Bugs:
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=====
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Please report all bugs to our issue tracker:
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http://code.google.com/p/webp/issues
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Patches welcome! See this page to get started:
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http://www.webmproject.org/code/contribute/submitting-patches/
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Discuss:
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========
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Email: webp-discuss@webmproject.org
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Web: http://groups.google.com/a/webmproject.org/group/webp-discuss
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