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   M40 = 1.0
  17 };
  18
  19 /**
  20  * Video decoder interface.
  21  *
  22  * Typical usage:
  23  * - Call Create() to create a new video decoder resource.
  24  * - Call Initialize() to initialize it with a 3d graphics context and the
  25  *   desired codec profile.
  26  * - Call Decode() continuously (waiting for each previous call to complete) to
  27  *   push bitstream buffers to the decoder.
  28  * - Call GetPicture() continuously (waiting for each previous call to complete)
  29  *   to pull decoded pictures from the decoder.
  30  * - Call Flush() to signal end of stream to the decoder and perform shutdown
  31  *   when it completes.
  32  * - Call Reset() to quickly stop the decoder (e.g. to implement Seek) and wait
  33  *   for the callback before restarting decoding at another point.
  34  * - To destroy the decoder, the plugin should release all of its references to
  35  *   it. Any pending callbacks will abort before the decoder is destroyed.
  36  *
  37  * Available video codecs vary by platform.
  38  * All: theora, vorbis, vp8.
  39  * Chrome and ChromeOS: aac, h264.
  40  * ChromeOS: mpeg4.
  41  */
  42 interface PPB_VideoDecoder {
  43   /**
  44    * Creates a new video decoder resource.
  45    *
  46    * @param[in] instance A <code>PP_Instance</code> identifying the instance
  47    * with the video decoder.
  48    *
  49    * @return A <code>PP_Resource</code> corresponding to a video decoder if
  50    * successful or 0 otherwise.
  51    */
  52   PP_Resource Create(
  53       [in] PP_Instance instance);
  54
  55   /**
  56    * Determines if the given resource is a video decoder.
  57    *
  58    * @param[in] resource A <code>PP_Resource</code> identifying a resource.
  59    *
  60    * @return <code>PP_TRUE</code> if the resource is a
  61    * <code>PPB_VideoDecoder</code>, <code>PP_FALSE</code> if the resource is
  62    * invalid or some other type.
  63    */
  64   PP_Bool IsVideoDecoder(
  65       [in] PP_Resource resource);
  66
  67   /**
  68    * Initializes a video decoder resource. This should be called after Create()
  69    * and before any other functions.
  70    *
  71    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
  72    * decoder.
  73    * @param[in] graphics3d_context A <code>PPB_Graphics3D</code> resource to use
  74    * during decoding.
  75    * @param[in] profile A <code>PP_VideoProfile</code> specifying the video
  76    * codec profile.
  77    * @param[in] allow_software_fallback A <code>PP_Bool</code> specifying
  78    * whether the decoder can fall back to software decoding if a suitable
  79    * hardware decoder isn't available.
  80    * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
  81    * completion.
  82    *
  83    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
  84    * Returns PP_ERROR_NOTSUPPORTED if video decoding is not available, or the
  85    * requested profile is not supported. In this case, the client may call
  86    * Initialize() again with different parameters to find a good configuration.
  87    */
  88   int32_t Initialize(
  89       [in] PP_Resource video_decoder,
  90       [in] PP_Resource graphics3d_context,
  91       [in] PP_VideoProfile profile,
  92       [in] PP_Bool allow_software_fallback,
  93       [in] PP_CompletionCallback callback);
  94
  95   /**
  96    * Initializes a video decoder resource. This should be called after Create()
  97    * and before any other functions.
  98    *
  99    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 100    * decoder.
 101    * @param[in] graphics3d_context A <code>PPB_Graphics3D</code> resource to use
 102    * during decoding.
 103    * @param[in] profile A <code>PP_VideoProfile</code> specifying the video
 104    * codec profile.
 105    * @param[in] acceleration A <code>PP_HardwareAcceleration</code> specifying
 106    * whether to use a hardware accelerated or a software implementation.
 107    * @param[in] callback A <code>PP_CompletionCallback</code> to be called upon
 108    * completion.
 109    *
 110    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 111    * Returns PP_ERROR_NOTSUPPORTED if video decoding is not available, or the
 112    * requested profile is not supported. In this case, the client may call
 113    * Initialize() again with different parameters to find a good configuration.
 114    */
 115   [version = 0.2]
 116   int32_t Initialize(
 117       [in] PP_Resource video_decoder,
 118       [in] PP_Resource graphics3d_context,
 119       [in] PP_VideoProfile profile,
 120       [in] PP_HardwareAcceleration acceleration,
 121       [in] PP_CompletionCallback callback);
 122
 123   /**
 124    * Decodes a bitstream buffer. Copies |size| bytes of data from the plugin's
 125    * |buffer|. The plugin should wait until the decoder signals completion by
 126    * returning PP_OK or by running |callback| before calling Decode() again.
 127    *
 128    * In general, each bitstream buffer should contain a demuxed bitstream frame
 129    * for the selected video codec. For example, H264 decoders expect to receive
 130    * one AnnexB NAL unit, including the 4 byte start code prefix, while VP8
 131    * decoders expect to receive a bitstream frame without the IVF frame header.
 132    *
 133    * If the call to Decode() eventually results in a picture, the |decode_id|
 134    * parameter is copied into the returned picture. The plugin can use this to
 135    * associate decoded pictures with Decode() calls (e.g. to assign timestamps
 136    * or frame numbers to pictures.) This value is opaque to the API so the
 137    * plugin is free to pass any value.
 138    *
 139    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 140    * decoder.
 141    * @param[in] decode_id An optional value, chosen by the plugin, that can be
 142    * used to associate calls to Decode() with decoded pictures returned by
 143    * GetPicture().
 144    * @param[in] size Buffer size in bytes.
 145    * @param[in] buffer Starting address of buffer.
 146    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 147    * completion.
 148    *
 149    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 150    * Returns PP_ERROR_FAILED if the decoder isn't initialized or if a Flush()
 151    * or Reset() call is pending.
 152    * Returns PP_ERROR_INPROGRESS if there is another Decode() call pending.
 153    * Returns PP_ERROR_NOMEMORY if a bitstream buffer can't be created.
 154    * Returns PP_ERROR_ABORTED when Reset() is called while Decode() is pending.
 155    */
 156   int32_t Decode(
 157       [in] PP_Resource video_decoder,
 158       [in] uint32_t decode_id,
 159       [in] uint32_t size,
 160       [in] mem_t buffer,
 161       [in] PP_CompletionCallback callback);
 162
 163   /**
 164    * Gets the next picture from the decoder. The picture is valid after the
 165    * decoder signals completion by returning PP_OK or running |callback|. The
 166    * plugin can call GetPicture() again after the decoder signals completion.
 167    * When the plugin is finished using the picture, it should return it to the
 168    * system by calling RecyclePicture().
 169    *
 170    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 171    * decoder.
 172    * @param[out] picture A <code>PP_VideoPicture</code> to hold the decoded
 173    * picture.
 174    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 175    * completion.
 176    *
 177    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 178    * Returns PP_ERROR_FAILED if the decoder isn't initialized or if a Reset()
 179    * call is pending.
 180    * Returns PP_ERROR_INPROGRESS if there is another GetPicture() call pending.
 181    * Returns PP_ERROR_ABORTED when Reset() is called, or if a call to Flush()
 182    * completes while GetPicture() is pending.
 183    */
 184   int32_t GetPicture(
 185       [in] PP_Resource video_decoder,
 186       [out] PP_VideoPicture_0_1 picture,
 187       [in] PP_CompletionCallback callback);
 188
 189   /**
 190    * Gets the next picture from the decoder. The picture is valid after the
 191    * decoder signals completion by returning PP_OK or running |callback|. The
 192    * plugin can call GetPicture() again after the decoder signals completion.
 193    * When the plugin is finished using the picture, it should return it to the
 194    * system by calling RecyclePicture().
 195    *
 196    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 197    * decoder.
 198    * @param[out] picture A <code>PP_VideoPicture</code> to hold the decoded
 199    * picture.
 200    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 201    * completion.
 202    *
 203    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 204    * Returns PP_ERROR_FAILED if the decoder isn't initialized or if a Reset()
 205    * call is pending.
 206    * Returns PP_ERROR_INPROGRESS if there is another GetPicture() call pending.
 207    * Returns PP_ERROR_ABORTED when Reset() is called, or if a call to Flush()
 208    * completes while GetPicture() is pending.
 209    */
 210   [version = 1.0]
 211   int32_t GetPicture(
 212       [in] PP_Resource video_decoder,
 213       [out] PP_VideoPicture picture,
 214       [in] PP_CompletionCallback callback);
 215
 216   /**
 217    * Recycles a picture that the plugin has received from the decoder.
 218    * The plugin should call this as soon as it has finished using the texture so
 219    * the decoder can decode more pictures.
 220    *
 221    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 222    * decoder.
 223    * @param[in] picture A <code>PP_VideoPicture</code> to return to
 224    * the decoder.
 225    */
 226   void RecyclePicture(
 227       [in] PP_Resource video_decoder,
 228       [in] PP_VideoPicture picture);
 229
 230   /**
 231    * Flushes the decoder. The plugin should call Flush() when it reaches the
 232    * end of its video stream in order to stop cleanly. The decoder will run any
 233    * pending Decode() call to completion. The plugin should make no further
 234    * calls to the decoder other than GetPicture() and RecyclePicture() until
 235    * the decoder signals completion by running |callback|. Just before
 236    * completion, any pending GetPicture() call will complete by running its
 237    * callback with result PP_ERROR_ABORTED to signal that no more pictures are
 238    * available. Any pictures held by the plugin remain valid during and after
 239    * the flush and should be recycled back to the decoder.
 240    *
 241    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 242    * decoder.
 243    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 244    * completion.
 245    *
 246    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 247    * Returns PP_ERROR_FAILED if the decoder isn't initialized.
 248    */
 249   int32_t Flush(
 250       [in] PP_Resource video_decoder,
 251       [in] PP_CompletionCallback callback);
 252
 253   /**
 254    * Resets the decoder as quickly as possible. The plugin can call Reset() to
 255    * skip to another position in the video stream. After Reset() returns, any
 256    * pending calls to Decode() and GetPicture()) abort, causing their callbacks
 257    * to run with PP_ERROR_ABORTED. The plugin should not make further calls to
 258    * the decoder other than RecyclePicture() until the decoder signals
 259    * completion by running |callback|. Any pictures held by the plugin remain
 260    * valid during and after the reset and should be recycled back to the
 261    * decoder.
 262    *
 263    * @param[in] video_decoder A <code>PP_Resource</code> identifying the video
 264    * decoder.
 265    * @param[in] callback A <code>PP_CompletionCallback</code> to be called on
 266    * completion.
 267    *
 268    * @return An int32_t containing an error code from <code>pp_errors.h</code>.
 269    * Returns PP_ERROR_FAILED if the decoder isn't initialized.
 270    */
 271   int32_t Reset(
 272       [in] PP_Resource video_decoder,
 273       [in] PP_CompletionCallback callback);
 274 };