vpx/vpx_decoder.h

   1 /*
   2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   3  *
   4  *  Use of this source code is governed by a BSD-style license
   5  *  that can be found in the LICENSE file in the root of the source
   6  *  tree. An additional intellectual property rights grant can be found
   7  *  in the file PATENTS.  All contributing project authors may
   8  *  be found in the AUTHORS file in the root of the source tree.
   9  */
  10 #ifndef VPX_VPX_DECODER_H_
  11 #define VPX_VPX_DECODER_H_
  12
  13 /*!\defgroup decoder Decoder Algorithm Interface
  14  * \ingroup codec
  15  * This abstraction allows applications using this decoder to easily support
  16  * multiple video formats with minimal code duplication. This section describes
  17  * the interface common to all decoders.
  18  * @{
  19  */
  20
  21 /*!\file
  22  * \brief Describes the decoder algorithm interface to applications.
  23  *
  24  * This file describes the interface between an application and a
  25  * video decoder algorithm.
  26  *
  27  */
  28 #ifdef __cplusplus
  29 extern "C" {
  30 #endif
  31
  32 #include "./vpx_codec.h"
  33 #include "./vpx_frame_buffer.h"
  34
  35   /*!\brief Current ABI version number
  36    *
  37    * \internal
  38    * If this file is altered in any way that changes the ABI, this value
  39    * must be bumped.  Examples include, but are not limited to, changing
  40    * types, removing or reassigning enums, adding/removing/rearranging
  41    * fields to structures
  42    */
  43 #define VPX_DECODER_ABI_VERSION (3 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/
  44
  45   /*! \brief Decoder capabilities bitfield
  46    *
  47    *  Each decoder advertises the capabilities it supports as part of its
  48    *  ::vpx_codec_iface_t interface structure. Capabilities are extra interfaces
  49    *  or functionality, and are not required to be supported by a decoder.
  50    *
  51    *  The available flags are specified by VPX_CODEC_CAP_* defines.
  52    */
  53 #define VPX_CODEC_CAP_PUT_SLICE  0x10000 /**< Will issue put_slice callbacks */
  54 #define VPX_CODEC_CAP_PUT_FRAME  0x20000 /**< Will issue put_frame callbacks */
  55 #define VPX_CODEC_CAP_POSTPROC   0x40000 /**< Can postprocess decoded frame */
  56 #define VPX_CODEC_CAP_ERROR_CONCEALMENT   0x80000 /**< Can conceal errors due to
  57   packet loss */
  58 #define VPX_CODEC_CAP_INPUT_FRAGMENTS   0x100000 /**< Can receive encoded frames
  59   one fragment at a time */
  60
  61   /*! \brief Initialization-time Feature Enabling
  62    *
  63    *  Certain codec features must be known at initialization time, to allow for
  64    *  proper memory allocation.
  65    *
  66    *  The available flags are specified by VPX_CODEC_USE_* defines.
  67    */
  68 #define VPX_CODEC_CAP_FRAME_THREADING   0x200000 /**< Can support frame-based
  69                                                       multi-threading */
  70 #define VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER 0x400000 /**< Can support external
  71                                                           frame buffers */
  72
  73 #define VPX_CODEC_USE_POSTPROC   0x10000 /**< Postprocess decoded frame */
  74 #define VPX_CODEC_USE_ERROR_CONCEALMENT 0x20000 /**< Conceal errors in decoded
  75   frames */
  76 #define VPX_CODEC_USE_INPUT_FRAGMENTS   0x40000 /**< The input frame should be
  77   passed to the decoder one
  78   fragment at a time */
  79 #define VPX_CODEC_USE_FRAME_THREADING   0x80000 /**< Enable frame-based
  80                                                      multi-threading */
  81
  82   /*!\brief Stream properties
  83    *
  84    * This structure is used to query or set properties of the decoded
  85    * stream. Algorithms may extend this structure with data specific
  86    * to their bitstream by setting the sz member appropriately.
  87    */
  88   typedef struct vpx_codec_stream_info {
  89     unsigned int sz;     /**< Size of this structure */
  90     unsigned int w;      /**< Width (or 0 for unknown/default) */
  91     unsigned int h;      /**< Height (or 0 for unknown/default) */
  92     unsigned int is_kf;  /**< Current frame is a keyframe */
  93   } vpx_codec_stream_info_t;
  94
  95   /* REQUIRED FUNCTIONS
  96    *
  97    * The following functions are required to be implemented for all decoders.
  98    * They represent the base case functionality expected of all decoders.
  99    */
 100
 101
 102   /*!\brief Initialization Configurations
 103    *
 104    * This structure is used to pass init time configuration options to the
 105    * decoder.
 106    */
 107   typedef struct vpx_codec_dec_cfg {
 108     unsigned int threads; /**< Maximum number of threads to use, default 1 */
 109     unsigned int w;      /**< Width */
 110     unsigned int h;      /**< Height */
 111   } vpx_codec_dec_cfg_t; /**< alias for struct vpx_codec_dec_cfg */
 112
 113
 114   /*!\brief Initialize a decoder instance
 115    *
 116    * Initializes a decoder context using the given interface. Applications
 117    * should call the vpx_codec_dec_init convenience macro instead of this
 118    * function directly, to ensure that the ABI version number parameter
 119    * is properly initialized.
 120    *
 121    * If the library was configured with --disable-multithread, this call
 122    * is not thread safe and should be guarded with a lock if being used
 123    * in a multithreaded context.
 124    *
 125    * \param[in]    ctx     Pointer to this instance's context.
 126    * \param[in]    iface   Pointer to the algorithm interface to use.
 127    * \param[in]    cfg     Configuration to use, if known. May be NULL.
 128    * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags
 129    * \param[in]    ver     ABI version number. Must be set to
 130    *                       VPX_DECODER_ABI_VERSION
 131    * \retval #VPX_CODEC_OK
 132    *     The decoder algorithm initialized.
 133    * \retval #VPX_CODEC_MEM_ERROR
 134    *     Memory allocation failed.
 135    */
 136   vpx_codec_err_t vpx_codec_dec_init_ver(vpx_codec_ctx_t      *ctx,
 137                                          vpx_codec_iface_t    *iface,
 138                                          const vpx_codec_dec_cfg_t *cfg,
 139                                          vpx_codec_flags_t     flags,
 140                                          int                   ver);
 141
 142   /*!\brief Convenience macro for vpx_codec_dec_init_ver()
 143    *
 144    * Ensures the ABI version parameter is properly set.
 145    */
 146 #define vpx_codec_dec_init(ctx, iface, cfg, flags) \
 147   vpx_codec_dec_init_ver(ctx, iface, cfg, flags, VPX_DECODER_ABI_VERSION)
 148
 149
 150   /*!\brief Parse stream info from a buffer
 151    *
 152    * Performs high level parsing of the bitstream. Construction of a decoder
 153    * context is not necessary. Can be used to determine if the bitstream is
 154    * of the proper format, and to extract information from the stream.
 155    *
 156    * \param[in]      iface   Pointer to the algorithm interface
 157    * \param[in]      data    Pointer to a block of data to parse
 158    * \param[in]      data_sz Size of the data buffer
 159    * \param[in,out]  si      Pointer to stream info to update. The size member
 160    *                         \ref MUST be properly initialized, but \ref MAY be
 161    *                         clobbered by the algorithm. This parameter \ref MAY
 162    *                         be NULL.
 163    *
 164    * \retval #VPX_CODEC_OK
 165    *     Bitstream is parsable and stream information updated
 166    */
 167   vpx_codec_err_t vpx_codec_peek_stream_info(vpx_codec_iface_t       *iface,
 168                                              const uint8_t           *data,
 169                                              unsigned int             data_sz,
 170                                              vpx_codec_stream_info_t *si);
 171
 172
 173   /*!\brief Return information about the current stream.
 174    *
 175    * Returns information about the stream that has been parsed during decoding.
 176    *
 177    * \param[in]      ctx     Pointer to this instance's context
 178    * \param[in,out]  si      Pointer to stream info to update. The size member
 179    *                         \ref MUST be properly initialized, but \ref MAY be
 180    *                         clobbered by the algorithm. This parameter \ref MAY
 181    *                         be NULL.
 182    *
 183    * \retval #VPX_CODEC_OK
 184    *     Bitstream is parsable and stream information updated
 185    */
 186   vpx_codec_err_t vpx_codec_get_stream_info(vpx_codec_ctx_t         *ctx,
 187                                             vpx_codec_stream_info_t *si);
 188
 189
 190   /*!\brief Decode data
 191    *
 192    * Processes a buffer of coded data. If the processing results in a new
 193    * decoded frame becoming available, PUT_SLICE and PUT_FRAME events may be
 194    * generated, as appropriate. Encoded data \ref MUST be passed in DTS (decode
 195    * time stamp) order. Frames produced will always be in PTS (presentation
 196    * time stamp) order.
 197    * If the decoder is configured with VPX_CODEC_USE_INPUT_FRAGMENTS enabled,
 198    * data and data_sz can contain a fragment of the encoded frame. Fragment
 199    * \#n must contain at least partition \#n, but can also contain subsequent
 200    * partitions (\#n+1 - \#n+i), and if so, fragments \#n+1, .., \#n+i must
 201    * be empty. When no more data is available, this function should be called
 202    * with NULL as data and 0 as data_sz. The memory passed to this function
 203    * must be available until the frame has been decoded.
 204    *
 205    * \param[in] ctx          Pointer to this instance's context
 206    * \param[in] data         Pointer to this block of new coded data. If
 207    *                         NULL, a VPX_CODEC_CB_PUT_FRAME event is posted
 208    *                         for the previously decoded frame.
 209    * \param[in] data_sz      Size of the coded data, in bytes.
 210    * \param[in] user_priv    Application specific data to associate with
 211    *                         this frame.
 212    * \param[in] deadline     Soft deadline the decoder should attempt to meet,
 213    *                         in us. Set to zero for unlimited.
 214    *
 215    * \return Returns #VPX_CODEC_OK if the coded data was processed completely
 216    *         and future pictures can be decoded without error. Otherwise,
 217    *         see the descriptions of the other error codes in ::vpx_codec_err_t
 218    *         for recoverability capabilities.
 219    */
 220   vpx_codec_err_t vpx_codec_decode(vpx_codec_ctx_t    *ctx,
 221                                    const uint8_t        *data,
 222                                    unsigned int            data_sz,
 223                                    void               *user_priv,
 224                                    long                deadline);
 225
 226
 227   /*!\brief Decoded frames iterator
 228    *
 229    * Iterates over a list of the frames available for display. The iterator
 230    * storage should be initialized to NULL to start the iteration. Iteration is
 231    * complete when this function returns NULL.
 232    *
 233    * The list of available frames becomes valid upon completion of the
 234    * vpx_codec_decode call, and remains valid until the next call to vpx_codec_decode.
 235    *
 236    * \param[in]     ctx      Pointer to this instance's context
 237    * \param[in,out] iter     Iterator storage, initialized to NULL
 238    *
 239    * \return Returns a pointer to an image, if one is ready for display. Frames
 240    *         produced will always be in PTS (presentation time stamp) order.
 241    */
 242   vpx_image_t *vpx_codec_get_frame(vpx_codec_ctx_t  *ctx,
 243                                    vpx_codec_iter_t *iter);
 244
 245
 246   /*!\defgroup cap_put_frame Frame-Based Decoding Functions
 247    *
 248    * The following functions are required to be implemented for all decoders
 249    * that advertise the VPX_CODEC_CAP_PUT_FRAME capability. Calling these functions
 250    * for codecs that don't advertise this capability will result in an error
 251    * code being returned, usually VPX_CODEC_ERROR
 252    * @{
 253    */
 254
 255   /*!\brief put frame callback prototype
 256    *
 257    * This callback is invoked by the decoder to notify the application of
 258    * the availability of decoded image data.
 259    */
 260   typedef void (*vpx_codec_put_frame_cb_fn_t)(void        *user_priv,
 261                                               const vpx_image_t *img);
 262
 263
 264   /*!\brief Register for notification of frame completion.
 265    *
 266    * Registers a given function to be called when a decoded frame is
 267    * available.
 268    *
 269    * \param[in] ctx          Pointer to this instance's context
 270    * \param[in] cb           Pointer to the callback function
 271    * \param[in] user_priv    User's private data
 272    *
 273    * \retval #VPX_CODEC_OK
 274    *     Callback successfully registered.
 275    * \retval #VPX_CODEC_ERROR
 276    *     Decoder context not initialized, or algorithm not capable of
 277    *     posting slice completion.
 278    */
 279   vpx_codec_err_t vpx_codec_register_put_frame_cb(vpx_codec_ctx_t             *ctx,
 280                                                   vpx_codec_put_frame_cb_fn_t  cb,
 281                                                   void                        *user_priv);
 282
 283
 284   /*!@} - end defgroup cap_put_frame */
 285
 286   /*!\defgroup cap_put_slice Slice-Based Decoding Functions
 287    *
 288    * The following functions are required to be implemented for all decoders
 289    * that advertise the VPX_CODEC_CAP_PUT_SLICE capability. Calling these functions
 290    * for codecs that don't advertise this capability will result in an error
 291    * code being returned, usually VPX_CODEC_ERROR
 292    * @{
 293    */
 294
 295   /*!\brief put slice callback prototype
 296    *
 297    * This callback is invoked by the decoder to notify the application of
 298    * the availability of partially decoded image data. The
 299    */
 300   typedef void (*vpx_codec_put_slice_cb_fn_t)(void         *user_priv,
 301                                               const vpx_image_t      *img,
 302                                               const vpx_image_rect_t *valid,
 303                                               const vpx_image_rect_t *update);
 304
 305
 306   /*!\brief Register for notification of slice completion.
 307    *
 308    * Registers a given function to be called when a decoded slice is
 309    * available.
 310    *
 311    * \param[in] ctx          Pointer to this instance's context
 312    * \param[in] cb           Pointer to the callback function
 313    * \param[in] user_priv    User's private data
 314    *
 315    * \retval #VPX_CODEC_OK
 316    *     Callback successfully registered.
 317    * \retval #VPX_CODEC_ERROR
 318    *     Decoder context not initialized, or algorithm not capable of
 319    *     posting slice completion.
 320    */
 321   vpx_codec_err_t vpx_codec_register_put_slice_cb(vpx_codec_ctx_t             *ctx,
 322                                                   vpx_codec_put_slice_cb_fn_t  cb,
 323                                                   void                        *user_priv);
 324
 325
 326   /*!@} - end defgroup cap_put_slice*/
 327
 328   /*!\defgroup cap_external_frame_buffer External Frame Buffer Functions
 329    *
 330    * The following section is required to be implemented for all decoders
 331    * that advertise the VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER capability.
 332    * Calling this function for codecs that don't advertise this capability
 333    * will result in an error code being returned, usually VPX_CODEC_ERROR.
 334    *
 335    * \note
 336    * Currently this only works with VP9.
 337    * @{
 338    */
 339
 340   /*!\brief Pass in external frame buffers for the decoder to use.
 341    *
 342    * Registers functions to be called when libvpx needs a frame buffer
 343    * to decode the current frame and a function to be called when libvpx does
 344    * not internally reference the frame buffer. This set function must
 345    * be called before the first call to decode or libvpx will assume the
 346    * default behavior of allocating frame buffers internally.
 347    *
 348    * \param[in] ctx          Pointer to this instance's context
 349    * \param[in] cb_get       Pointer to the get callback function
 350    * \param[in] cb_release   Pointer to the release callback function
 351    * \param[in] cb_priv      Callback's private data
 352    *
 353    * \retval #VPX_CODEC_OK
 354    *     External frame buffers will be used by libvpx.
 355    * \retval #VPX_CODEC_INVALID_PARAM
 356    *     One or more of the callbacks were NULL.
 357    * \retval #VPX_CODEC_ERROR
 358    *     Decoder context not initialized, or algorithm not capable of
 359    *     using external frame buffers.
 360    *
 361    * \note
 362    * When decoding VP9, the application may be required to pass in at least
 363    * #VP9_MAXIMUM_REF_BUFFERS + #VPX_MAXIMUM_WORK_BUFFERS external frame
 364    * buffers.
 365    */
 366   vpx_codec_err_t vpx_codec_set_frame_buffer_functions(
 367       vpx_codec_ctx_t *ctx,
 368       vpx_get_frame_buffer_cb_fn_t cb_get,
 369       vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv);
 370
 371   /*!@} - end defgroup cap_external_frame_buffer */
 372
 373   /*!@} - end defgroup decoder*/
 374 #ifdef __cplusplus
 375 }
 376 #endif
 377 #endif  // VPX_VPX_DECODER_H_
 378