ref: 188d58eaa99ed5b47af77b354e303a82614ce62a
dir: /vpx/vpx_decoder.h/
/* * 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_VPX_DECODER_H_ #define VPX_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" #include "./vpx_frame_buffer.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 \ (3 + 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 */ /*!\brief Can conceal errors due to packet loss */ #define VPX_CODEC_CAP_ERROR_CONCEALMENT 0x80000 /*!\brief Can receive encoded frames one fragment at a time */ #define VPX_CODEC_CAP_INPUT_FRAGMENTS 0x100000 /*! \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. */ /*!\brief Can support frame-based multi-threading */ #define VPX_CODEC_CAP_FRAME_THREADING 0x200000 /*!brief Can support external frame buffers */ #define VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER 0x400000 #define VPX_CODEC_USE_POSTPROC 0x10000 /**< Postprocess decoded frame */ /*!\brief Conceal errors in decoded frames */ #define VPX_CODEC_USE_ERROR_CONCEALMENT 0x20000 /*!\brief The input frame should be passed to the decoder one fragment at a * time */ #define VPX_CODEC_USE_INPUT_FRAGMENTS 0x40000 /*!\brief Enable frame-based multi-threading */ #define VPX_CODEC_USE_FRAME_THREADING 0x80000 /*!\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. * * \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, const 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*/ /*!\defgroup cap_external_frame_buffer External Frame Buffer Functions * * The following section is required to be implemented for all decoders * that advertise the VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER capability. * Calling this function for codecs that don't advertise this capability * will result in an error code being returned, usually VPX_CODEC_ERROR. * * \note * Currently this only works with VP9. * @{ */ /*!\brief Pass in external frame buffers for the decoder to use. * * Registers functions to be called when libvpx needs a frame buffer * to decode the current frame and a function to be called when libvpx does * not internally reference the frame buffer. This set function must * be called before the first call to decode or libvpx will assume the * default behavior of allocating frame buffers internally. * * \param[in] ctx Pointer to this instance's context * \param[in] cb_get Pointer to the get callback function * \param[in] cb_release Pointer to the release callback function * \param[in] cb_priv Callback's private data * * \retval #VPX_CODEC_OK * External frame buffers will be used by libvpx. * \retval #VPX_CODEC_INVALID_PARAM * One or more of the callbacks were NULL. * \retval #VPX_CODEC_ERROR * Decoder context not initialized, or algorithm not capable of * using external frame buffers. * * \note * When decoding VP9, the application may be required to pass in at least * #VP9_MAXIMUM_REF_BUFFERS + #VPX_MAXIMUM_WORK_BUFFERS external frame * buffers. */ vpx_codec_err_t vpx_codec_set_frame_buffer_functions( vpx_codec_ctx_t *ctx, vpx_get_frame_buffer_cb_fn_t cb_get, vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv); /*!@} - end defgroup cap_external_frame_buffer */ /*!@} - end defgroup decoder*/ #ifdef __cplusplus } #endif #endif // VPX_VPX_DECODER_H_