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 /*

  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.

  *

  *  Use of this source code is governed by a BSD-style license

  *  that can be found in the LICENSE file in the root of the source

  *  tree. An additional intellectual property rights grant can be found

  *  in the file PATENTS.  All contributing project authors may

  *  be found in the AUTHORS file in the root of the source tree.

  */

 #ifndef VPX_DECODER_H

 #define VPX_DECODER_H

 /*!\defgroup decoder Decoder Algorithm Interface

  * \ingroup codec

  * This abstraction allows applications using this decoder to easily support

  * multiple video formats with minimal code duplication. This section describes

  * the interface common to all decoders.

  * @{

  */

 /*!\file

  * \brief Describes the decoder algorithm interface to applications.

  *

  * This file describes the interface between an application and a

  * video decoder algorithm.

  *

  */

 #ifdef __cplusplus

 extern "C" {

 #endif

 #include "vpx_codec.h"

   /*!\brief Current ABI version number

    *

    * \internal

    * If this file is altered in any way that changes the ABI, this value

    * must be bumped.  Examples include, but are not limited to, changing

    * types, removing or reassigning enums, adding/removing/rearranging

    * fields to structures

    */

 #define VPX_DECODER_ABI_VERSION (2 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/

   /*! \brief Decoder capabilities bitfield

    *

    *  Each decoder advertises the capabilities it supports as part of its

    *  ::vpx_codec_iface_t interface structure. Capabilities are extra interfaces

    *  or functionality, and are not required to be supported by a decoder.

    *

    *  The available flags are specified by VPX_CODEC_CAP_* defines.

    */

 #define VPX_CODEC_CAP_PUT_SLICE  0x10000 /**< Will issue put_slice callbacks */

 #define VPX_CODEC_CAP_PUT_FRAME  0x20000 /**< Will issue put_frame callbacks */

 #define VPX_CODEC_CAP_POSTPROC   0x40000 /**< Can postprocess decoded frame */

 #define VPX_CODEC_CAP_ERROR_CONCEALMENT   0x80000 /**< Can conceal errors due to

   packet loss */

 #define VPX_CODEC_CAP_INPUT_FRAGMENTS   0x100000 /**< Can receive encoded frames

   one fragment at a time */

   /*! \brief Initialization-time Feature Enabling

    *

    *  Certain codec features must be known at initialization time, to allow for

    *  proper memory allocation.

    *

    *  The available flags are specified by VPX_CODEC_USE_* defines.

    */

 #define VPX_CODEC_CAP_FRAME_THREADING   0x200000 /**< Can support frame-based

                                                       multi-threading */

 #define VPX_CODEC_USE_POSTPROC   0x10000 /**< Postprocess decoded frame */

 #define VPX_CODEC_USE_ERROR_CONCEALMENT 0x20000 /**< Conceal errors in decoded

   frames */

 #define VPX_CODEC_USE_INPUT_FRAGMENTS   0x40000 /**< The input frame should be

   passed to the decoder one

   fragment at a time */

 #define VPX_CODEC_USE_FRAME_THREADING   0x80000 /**< Enable frame-based

                                                      multi-threading */

   /*!\brief Stream properties

    *

    * This structure is used to query or set properties of the decoded

    * stream. Algorithms may extend this structure with data specific

    * to their bitstream by setting the sz member appropriately.

    */

   typedef struct vpx_codec_stream_info {

     unsigned int sz;     /**< Size of this structure */

     unsigned int w;      /**< Width (or 0 for unknown/default) */

     unsigned int h;      /**< Height (or 0 for unknown/default) */

     unsigned int is_kf;  /**< Current frame is a keyframe */

   } vpx_codec_stream_info_t;

   /* REQUIRED FUNCTIONS

    *

    * The following functions are required to be implemented for all decoders.

    * They represent the base case functionality expected of all decoders.

    */

   /*!\brief Initialization Configurations

    *

    * This structure is used to pass init time configuration options to the

    * decoder.

    */

   typedef struct vpx_codec_dec_cfg {

     unsigned int threads; /**< Maximum number of threads to use, default 1 */

     unsigned int w;      /**< Width */

     unsigned int h;      /**< Height */

   } vpx_codec_dec_cfg_t; /**< alias for struct vpx_codec_dec_cfg */

   /*!\brief Initialize a decoder instance

    *

    * Initializes a decoder context using the given interface. Applications

    * should call the vpx_codec_dec_init convenience macro instead of this

    * function directly, to ensure that the ABI version number parameter

    * is properly initialized.

    *

    * If the library was configured with --disable-multithread, this call

    * is not thread safe and should be guarded with a lock if being used

    * in a multithreaded context.

    *

    * In XMA mode (activated by setting VPX_CODEC_USE_XMA in the flags

    * parameter), the storage pointed to by the cfg parameter must be

    * kept readable and stable until all memory maps have been set.

    *

    * \param[in]    ctx     Pointer to this instance's context.

    * \param[in]    iface   Pointer to the algorithm interface to use.

    * \param[in]    cfg     Configuration to use, if known. May be NULL.

    * \param[in]    flags   Bitfield of VPX_CODEC_USE_* flags

    * \param[in]    ver     ABI version number. Must be set to

    *                       VPX_DECODER_ABI_VERSION

    * \retval #VPX_CODEC_OK

    *     The decoder algorithm initialized.

    * \retval #VPX_CODEC_MEM_ERROR

    *     Memory allocation failed.

    */

   vpx_codec_err_t vpx_codec_dec_init_ver(vpx_codec_ctx_t      *ctx,

                                          vpx_codec_iface_t    *iface,

                                          vpx_codec_dec_cfg_t  *cfg,

                                          vpx_codec_flags_t     flags,

                                          int                   ver);

   /*!\brief Convenience macro for vpx_codec_dec_init_ver()

    *

    * Ensures the ABI version parameter is properly set.

    */

 #define vpx_codec_dec_init(ctx, iface, cfg, flags) \

   vpx_codec_dec_init_ver(ctx, iface, cfg, flags, VPX_DECODER_ABI_VERSION)

   /*!\brief Parse stream info from a buffer

    *

    * Performs high level parsing of the bitstream. Construction of a decoder

    * context is not necessary. Can be used to determine if the bitstream is

    * of the proper format, and to extract information from the stream.

    *

    * \param[in]      iface   Pointer to the algorithm interface

    * \param[in]      data    Pointer to a block of data to parse

    * \param[in]      data_sz Size of the data buffer

    * \param[in,out]  si      Pointer to stream info to update. The size member

    *                         \ref MUST be properly initialized, but \ref MAY be

    *                         clobbered by the algorithm. This parameter \ref MAY

    *                         be NULL.

    *

    * \retval #VPX_CODEC_OK

    *     Bitstream is parsable and stream information updated

    */

   vpx_codec_err_t vpx_codec_peek_stream_info(vpx_codec_iface_t       *iface,

                                              const uint8_t           *data,

                                              unsigned int             data_sz,

                                              vpx_codec_stream_info_t *si);

   /*!\brief Return information about the current stream.

    *

    * Returns information about the stream that has been parsed during decoding.

    *

    * \param[in]      ctx     Pointer to this instance's context

    * \param[in,out]  si      Pointer to stream info to update. The size member

    *                         \ref MUST be properly initialized, but \ref MAY be

    *                         clobbered by the algorithm. This parameter \ref MAY

    *                         be NULL.

    *

    * \retval #VPX_CODEC_OK

    *     Bitstream is parsable and stream information updated

    */

   vpx_codec_err_t vpx_codec_get_stream_info(vpx_codec_ctx_t         *ctx,

                                             vpx_codec_stream_info_t *si);

   /*!\brief Decode data

    *

    * Processes a buffer of coded data. If the processing results in a new

    * decoded frame becoming available, PUT_SLICE and PUT_FRAME events may be

    * generated, as appropriate. Encoded data \ref MUST be passed in DTS (decode

    * time stamp) order. Frames produced will always be in PTS (presentation

    * time stamp) order.

    * If the decoder is configured with VPX_CODEC_USE_INPUT_FRAGMENTS enabled,

    * data and data_sz can contain a fragment of the encoded frame. Fragment

    * \#n must contain at least partition \#n, but can also contain subsequent

    * partitions (\#n+1 - \#n+i), and if so, fragments \#n+1, .., \#n+i must

    * be empty. When no more data is available, this function should be called

    * with NULL as data and 0 as data_sz. The memory passed to this function

    * must be available until the frame has been decoded.

    *

    * \param[in] ctx          Pointer to this instance's context

    * \param[in] data         Pointer to this block of new coded data. If

    *                         NULL, a VPX_CODEC_CB_PUT_FRAME event is posted

    *                         for the previously decoded frame.

    * \param[in] data_sz      Size of the coded data, in bytes.

    * \param[in] user_priv    Application specific data to associate with

    *                         this frame.

    * \param[in] deadline     Soft deadline the decoder should attempt to meet,

    *                         in us. Set to zero for unlimited.

    *

    * \return Returns #VPX_CODEC_OK if the coded data was processed completely

    *         and future pictures can be decoded without error. Otherwise,

    *         see the descriptions of the other error codes in ::vpx_codec_err_t

    *         for recoverability capabilities.

    */

   vpx_codec_err_t vpx_codec_decode(vpx_codec_ctx_t    *ctx,

                                    const uint8_t        *data,

                                    unsigned int            data_sz,

                                    void               *user_priv,

                                    long                deadline);

   /*!\brief Decoded frames iterator

    *

    * Iterates over a list of the frames available for display. The iterator

    * storage should be initialized to NULL to start the iteration. Iteration is

    * complete when this function returns NULL.

    *

    * The list of available frames becomes valid upon completion of the

    * vpx_codec_decode call, and remains valid until the next call to vpx_codec_decode.

    *

    * \param[in]     ctx      Pointer to this instance's context

    * \param[in,out] iter     Iterator storage, initialized to NULL

    *

    * \return Returns a pointer to an image, if one is ready for display. Frames

    *         produced will always be in PTS (presentation time stamp) order.

    */

   vpx_image_t *vpx_codec_get_frame(vpx_codec_ctx_t  *ctx,

                                    vpx_codec_iter_t *iter);

   /*!\defgroup cap_put_frame Frame-Based Decoding Functions

    *

    * The following functions are required to be implemented for all decoders

    * that advertise the VPX_CODEC_CAP_PUT_FRAME capability. Calling these functions

    * for codecs that don't advertise this capability will result in an error

    * code being returned, usually VPX_CODEC_ERROR

    * @{

    */

   /*!\brief put frame callback prototype

    *

    * This callback is invoked by the decoder to notify the application of

    * the availability of decoded image data.

    */

   typedef void (*vpx_codec_put_frame_cb_fn_t)(void        *user_priv,

                                               const vpx_image_t *img);

   /*!\brief Register for notification of frame completion.

    *

    * Registers a given function to be called when a decoded frame is

    * available.

    *

    * \param[in] ctx          Pointer to this instance's context

    * \param[in] cb           Pointer to the callback function

    * \param[in] user_priv    User's private data

    *

    * \retval #VPX_CODEC_OK

    *     Callback successfully registered.

    * \retval #VPX_CODEC_ERROR

    *     Decoder context not initialized, or algorithm not capable of

    *     posting slice completion.

    */

   vpx_codec_err_t vpx_codec_register_put_frame_cb(vpx_codec_ctx_t             *ctx,

                                                   vpx_codec_put_frame_cb_fn_t  cb,

                                                   void                        *user_priv);

   /*!@} - end defgroup cap_put_frame */

   /*!\defgroup cap_put_slice Slice-Based Decoding Functions

    *

    * The following functions are required to be implemented for all decoders

    * that advertise the VPX_CODEC_CAP_PUT_SLICE capability. Calling these functions

    * for codecs that don't advertise this capability will result in an error

    * code being returned, usually VPX_CODEC_ERROR

    * @{

    */

   /*!\brief put slice callback prototype

    *

    * This callback is invoked by the decoder to notify the application of

    * the availability of partially decoded image data. The

    */

   typedef void (*vpx_codec_put_slice_cb_fn_t)(void         *user_priv,

                                               const vpx_image_t      *img,

                                               const vpx_image_rect_t *valid,

                                               const vpx_image_rect_t *update);

   /*!\brief Register for notification of slice completion.

    *

    * Registers a given function to be called when a decoded slice is

    * available.

    *

    * \param[in] ctx          Pointer to this instance's context

    * \param[in] cb           Pointer to the callback function

    * \param[in] user_priv    User's private data

    *

    * \retval #VPX_CODEC_OK

    *     Callback successfully registered.

    * \retval #VPX_CODEC_ERROR

    *     Decoder context not initialized, or algorithm not capable of

    *     posting slice completion.

    */

   vpx_codec_err_t vpx_codec_register_put_slice_cb(vpx_codec_ctx_t             *ctx,

                                                   vpx_codec_put_slice_cb_fn_t  cb,

                                                   void                        *user_priv);

   /*!@} - end defgroup cap_put_slice*/

   /*!@} - end defgroup decoder*/

 #ifdef __cplusplus

 }

 #endif

 #endif