ppapi/api/ppb_video_decoder.idl

   1 /* Copyright (c) 2014 The Chromium Authors. All rights reserved.
   2  * Use of this source code is governed by a BSD-style license that can be
   3  * found in the LICENSE file.
   4  */
   5
   6 /**
   7  * This file defines the <code>PPB_VideoDecoder</code> interface.
   8  */
   9
  10 [generate_thunk]
  11
  12 label Chrome {
  13   /** Though not labeled 'channel=dev', 0.1 is a still a 'Dev' only API. */
  14   M36 = 0.1,
  15   M39 = 0.2
  16 };
  17
  18 /**
  19  * Video decoder interface.
  20  *
  21  * Typical usage:
  22  * - Call Create() to create a new video decoder resource.
  23  * - Call Initialize() to initialize it with a 3d graphics context and the
  24  *   desired codec profile.
  25  * - Call Decode() continuously (waiting for each previous call to complete) to
  26  *   push bitstream buffers to the decoder.
  27  * - Call GetPicture() continuously (waiting for each previous call to complete)
  28  *   to pull decoded pictures from the decoder.
  29  * - Call Flush() to signal end of stream to the decoder and perform shutdown
  30  *   when it completes.
  31  * - Call Reset() to quickly stop the decoder (e.g. to implement Seek) and wait
  32  *   for the callback before restarting decoding at another point.
  33  * - To destroy the decoder, the plugin should release all of its references to
  34  *   it. Any pending callbacks will abort before the decoder is destroyed.
  35  *
  36  * Available video codecs vary by platform.
  37  * All: theora, vorbis, vp8.
  38  * Chrome and ChromeOS: aac, h264.
  39  * ChromeOS: mpeg4.
  40  */
  41 interface PPB_VideoDecoder {
  42   /**
  43    * Creates a new video decoder resource.
  44    *
  45    * @param[in] instance A <code>PP_Instance</code> identifying the instance
  46    * with the video decoder.
  47    *
  48    * @return A <code>PP_Resource</code> corresponding to a video decoder if
  49    * successful or 0 otherwise.
  50    */
  51   PP_Resource Create(
  52       [in] PP_Instance instance);
  53
  54   /**
  55    * Determines if the given resource is a video decoder.
  56    *
  57    * @param[in] resource A <code>PP_Resource</code> identifying a resource.
  58    *
  59    * @return <code>PP_TRUE</code> if the resource is a
  60    * <code>PPB_VideoDecoder</code>, <code>PP_FALSE</code> if the resource is
  61    * invalid or some other type.
  62    */
  63   PP_Bool IsVideoDecoder(
  64       [in] PP_Resource resource);
  65
  66   /**
  67    * Initializes a video decoder resource. This should be called after Create()
  68    * and before any other functions.
  69    *
  70    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
  71    * decoder.
  72    * @param[in] graphics3d_context A <code>PPB_Graphics3D</code> resource to use
  73    * during decoding.
  74    * @param[in] profile A <code>PP_VideoProfile</code> specifying the video
  75    * codec profile.
  76    * @param[in] allow_software_fallback A <code>PP_Bool</code> specifying
  77    * whether the decoder can fall back to software decoding if a suitable
  78    * hardware decoder isn't available.
  79    * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
  80    * completion.
  81    *
  82    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
  83    * Returns PP_ERROR_NOTSUPPORTED if video decoding is not available, or the
  84    * requested profile is not supported. In this case, the client may call
  85    * Initialize() again with different parameters to find a good configuration.
  86    */
  87   int32_t Initialize(
  88       [in] PP_Resource video_decoder,
  89       [in] PP_Resource graphics3d_context,
  90       [in] PP_VideoProfile profile,
  91       [in] PP_Bool allow_software_fallback,
  92       [in] PP_CompletionCallback callback);
  93
  94   /**
  95    * Initializes a video decoder resource. This should be called after Create()
  96    * and before any other functions.
  97    *
  98    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
  99    * decoder.
 100    * @param[in] graphics3d_context A <code>PPB_Graphics3D</code> resource to use
 101    * during decoding.
 102    * @param[in] profile A <code>PP_VideoProfile</code> specifying the video
 103    * codec profile.
 104    * @param[in] acceleration A <code>PP_HardwareAcceleration</code> specifying
 105    * whether to use a hardware accelerated or a software implementation.
 106    * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
 107    * completion.
 108    *
 109    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 110    * Returns PP_ERROR_NOTSUPPORTED if video decoding is not available, or the
 111    * requested profile is not supported. In this case, the client may call
 112    * Initialize() again with different parameters to find a good configuration.
 113    */
 114   [version = 0.2]
 115   int32_t Initialize(
 116       [in] PP_Resource video_decoder,
 117       [in] PP_Resource graphics3d_context,
 118       [in] PP_VideoProfile profile,
 119       [in] PP_HardwareAcceleration acceleration,
 120       [in] PP_CompletionCallback callback);
 121
 122   /**
 123    * Decodes a bitstream buffer. Copies |size| bytes of data from the plugin's
 124    * |buffer|. The plugin should wait until the decoder signals completion by
 125    * returning PP_OK or by running |callback| before calling Decode() again.
 126    *
 127    * In general, each bitstream buffer should contain a demuxed bitstream frame
 128    * for the selected video codec. For example, H264 decoders expect to receive
 129    * one AnnexB NAL unit, including the 4 byte start code prefix, while VP8
 130    * decoders expect to receive a bitstream frame without the IVF frame header.
 131    *
 132    * If the call to Decode() eventually results in a picture, the |decode_id|
 133    * parameter is copied into the returned picture. The plugin can use this to
 134    * associate decoded pictures with Decode() calls (e.g. to assign timestamps
 135    * or frame numbers to pictures.) This value is opaque to the API so the
 136    * plugin is free to pass any value.
 137    *
 138    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 139    * decoder.
 140    * @param[in] decode_id An optional value, chosen by the plugin, that can be
 141    * used to associate calls to Decode() with decoded pictures returned by
 142    * GetPicture().
 143    * @param[in] size Buffer size in bytes.
 144    * @param[in] buffer Starting address of buffer.
 145    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 146    * completion.
 147    *
 148    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 149    * Returns PP_ERROR_FAILED if the decoder isn't initialized or if a Flush()
 150    * or Reset() call is pending.
 151    * Returns PP_ERROR_INPROGRESS if there is another Decode() call pending.
 152    * Returns PP_ERROR_NOMEMORY if a bitstream buffer can't be created.
 153    * Returns PP_ERROR_ABORTED when Reset() is called while Decode() is pending.
 154    */
 155   int32_t Decode(
 156       [in] PP_Resource video_decoder,
 157       [in] uint32_t decode_id,
 158       [in] uint32_t size,
 159       [in] mem_t buffer,
 160       [in] PP_CompletionCallback callback);
 161
 162   /**
 163    * Gets the next picture from the decoder. The picture is valid after the
 164    * decoder signals completion by returning PP_OK or running |callback|. The
 165    * plugin can call GetPicture() again after the decoder signals completion.
 166    * When the plugin is finished using the picture, it should return it to the
 167    * system by calling RecyclePicture().
 168    *
 169    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 170    * decoder.
 171    * @param[out] picture A <code>PP_VideoPicture</code> to hold the decoded
 172    * picture.
 173    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 174    * completion.
 175    *
 176    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 177    * Returns PP_ERROR_FAILED if the decoder isn't initialized or if a Reset()
 178    * call is pending.
 179    * Returns PP_ERROR_INPROGRESS if there is another GetPicture() call pending.
 180    * Returns PP_ERROR_ABORTED when Reset() is called, or if a call to Flush()
 181    * completes while GetPicture() is pending.
 182    */
 183   int32_t GetPicture(
 184       [in] PP_Resource video_decoder,
 185       [out] PP_VideoPicture picture,
 186       [in] PP_CompletionCallback callback);
 187
 188   /**
 189    * Recycles a picture that the plugin has received from the decoder.
 190    * The plugin should call this as soon as it has finished using the texture so
 191    * the decoder can decode more pictures.
 192    *
 193    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 194    * decoder.
 195    * @param[in] picture A <code>PP_VideoPicture</code> to return to
 196    * the decoder.
 197    */
 198   void RecyclePicture(
 199       [in] PP_Resource video_decoder,
 200       [in] PP_VideoPicture picture);
 201
 202   /**
 203    * Flushes the decoder. The plugin should call Flush() when it reaches the
 204    * end of its video stream in order to stop cleanly. The decoder will run any
 205    * pending Decode() call to completion. The plugin should make no further
 206    * calls to the decoder other than GetPicture() and RecyclePicture() until
 207    * the decoder signals completion by running |callback|. Just before
 208    * completion, any pending GetPicture() call will complete by running its
 209    * callback with result PP_ERROR_ABORTED to signal that no more pictures are
 210    * available. Any pictures held by the plugin remain valid during and after
 211    * the flush and should be recycled back to the decoder.
 212    *
 213    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 214    * decoder.
 215    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 216    * completion.
 217    *
 218    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 219    * Returns PP_ERROR_FAILED if the decoder isn't initialized.
 220    */
 221   int32_t Flush(
 222       [in] PP_Resource video_decoder,
 223       [in] PP_CompletionCallback callback);
 224
 225   /**
 226    * Resets the decoder as quickly as possible. The plugin can call Reset() to
 227    * skip to another position in the video stream. After Reset() returns, any
 228    * pending calls to Decode() and GetPicture()) abort, causing their callbacks
 229    * to run with PP_ERROR_ABORTED. The plugin should not make further calls to
 230    * the decoder other than RecyclePicture() until the decoder signals
 231    * completion by running |callback|. Any pictures held by the plugin remain
 232    * valid during and after the reset and should be recycled back to the
 233    * decoder.
 234    *
 235    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 236    * decoder.
 237    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 238    * completion.
 239    *
 240    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 241    * Returns PP_ERROR_FAILED if the decoder isn't initialized.
 242    */
 243   int32_t Reset(
 244       [in] PP_Resource video_decoder,
 245       [in] PP_CompletionCallback callback);
 246 };