2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
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.
10 #ifndef VPX_VPX_VPX_DECODER_H_
11 #define VPX_VPX_VPX_DECODER_H_
13 /*!\defgroup decoder Decoder Algorithm Interface
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.
22 * \brief Describes the decoder algorithm interface to applications.
24 * This file describes the interface between an application and a
25 * video decoder algorithm.
32 #include "./vpx_codec.h"
33 #include "./vpx_frame_buffer.h"
35 /*!\brief Current ABI version number
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
43 #define VPX_DECODER_ABI_VERSION \
44 (3 + VPX_CODEC_ABI_VERSION) /**<\hideinitializer*/
46 /*! \brief Decoder capabilities bitfield
48 * Each decoder advertises the capabilities it supports as part of its
49 * ::vpx_codec_iface_t interface structure. Capabilities are extra interfaces
50 * or functionality, and are not required to be supported by a decoder.
52 * The available flags are specified by VPX_CODEC_CAP_* defines.
54 #define VPX_CODEC_CAP_PUT_SLICE 0x10000 /**< Will issue put_slice callbacks */
55 #define VPX_CODEC_CAP_PUT_FRAME 0x20000 /**< Will issue put_frame callbacks */
56 #define VPX_CODEC_CAP_POSTPROC 0x40000 /**< Can postprocess decoded frame */
57 /*!\brief Can conceal errors due to packet loss */
58 #define VPX_CODEC_CAP_ERROR_CONCEALMENT 0x80000
59 /*!\brief Can receive encoded frames one fragment at a time */
60 #define VPX_CODEC_CAP_INPUT_FRAGMENTS 0x100000
61 /*!\brief Can support frame-based multi-threading */
62 #define VPX_CODEC_CAP_FRAME_THREADING 0x200000
63 /*!brief Can support external frame buffers */
64 #define VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER 0x400000
66 /*! \brief Initialization-time Feature Enabling
68 * Certain codec features must be known at initialization time, to allow for
69 * proper memory allocation.
71 * The available flags are specified by VPX_CODEC_USE_* defines.
73 #define VPX_CODEC_USE_POSTPROC 0x10000 /**< Postprocess decoded frame */
74 /*!\brief Conceal errors in decoded frames */
75 #define VPX_CODEC_USE_ERROR_CONCEALMENT 0x20000
76 /*!\brief The input frame should be passed to the decoder one fragment at a
78 #define VPX_CODEC_USE_INPUT_FRAGMENTS 0x40000
79 /*!\brief Enable frame-based multi-threading */
80 #define VPX_CODEC_USE_FRAME_THREADING 0x80000
82 /*!\brief Stream properties
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.
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;
97 * The following functions are required to be implemented for all decoders.
98 * They represent the base case functionality expected of all decoders.
101 /*!\brief Initialization Configurations
103 * This structure is used to pass init time configuration options to the
106 typedef struct vpx_codec_dec_cfg {
107 unsigned int threads; /**< Maximum number of threads to use, default 1 */
108 unsigned int w; /**< Width */
109 unsigned int h; /**< Height */
110 } vpx_codec_dec_cfg_t; /**< alias for struct vpx_codec_dec_cfg */
112 /*!\brief Initialize a decoder instance
114 * Initializes a decoder context using the given interface. Applications
115 * should call the vpx_codec_dec_init convenience macro instead of this
116 * function directly, to ensure that the ABI version number parameter
117 * is properly initialized.
119 * If the library was configured with --disable-multithread, this call
120 * is not thread safe and should be guarded with a lock if being used
121 * in a multithreaded context.
123 * \param[in] ctx Pointer to this instance's context.
124 * \param[in] iface Pointer to the algorithm interface to use.
125 * \param[in] cfg Configuration to use, if known. May be NULL.
126 * \param[in] flags Bitfield of VPX_CODEC_USE_* flags
127 * \param[in] ver ABI version number. Must be set to
128 * VPX_DECODER_ABI_VERSION
129 * \retval #VPX_CODEC_OK
130 * The decoder algorithm initialized.
131 * \retval #VPX_CODEC_MEM_ERROR
132 * Memory allocation failed.
134 vpx_codec_err_t vpx_codec_dec_init_ver(vpx_codec_ctx_t *ctx,
135 vpx_codec_iface_t *iface,
136 const vpx_codec_dec_cfg_t *cfg,
137 vpx_codec_flags_t flags, int ver);
139 /*!\brief Convenience macro for vpx_codec_dec_init_ver()
141 * Ensures the ABI version parameter is properly set.
143 #define vpx_codec_dec_init(ctx, iface, cfg, flags) \
144 vpx_codec_dec_init_ver(ctx, iface, cfg, flags, VPX_DECODER_ABI_VERSION)
146 /*!\brief Parse stream info from a buffer
148 * Performs high level parsing of the bitstream. Construction of a decoder
149 * context is not necessary. Can be used to determine if the bitstream is
150 * of the proper format, and to extract information from the stream.
152 * \param[in] iface Pointer to the algorithm interface
153 * \param[in] data Pointer to a block of data to parse
154 * \param[in] data_sz Size of the data buffer
155 * \param[in,out] si Pointer to stream info to update. The size member
156 * \ref MUST be properly initialized, but \ref MAY be
157 * clobbered by the algorithm. This parameter \ref MAY
160 * \retval #VPX_CODEC_OK
161 * Bitstream is parsable and stream information updated
163 vpx_codec_err_t vpx_codec_peek_stream_info(vpx_codec_iface_t *iface,
165 unsigned int data_sz,
166 vpx_codec_stream_info_t *si);
168 /*!\brief Return information about the current stream.
170 * Returns information about the stream that has been parsed during decoding.
172 * \param[in] ctx Pointer to this instance's context
173 * \param[in,out] si Pointer to stream info to update. The size member
174 * \ref MUST be properly initialized, but \ref MAY be
175 * clobbered by the algorithm. This parameter \ref MAY
178 * \retval #VPX_CODEC_OK
179 * Bitstream is parsable and stream information updated
181 vpx_codec_err_t vpx_codec_get_stream_info(vpx_codec_ctx_t *ctx,
182 vpx_codec_stream_info_t *si);
184 /*!\brief Decode data
186 * Processes a buffer of coded data. If the processing results in a new
187 * decoded frame becoming available, put_slice and put_frame callbacks may be
188 * invoked, as appropriate. Encoded data \ref MUST be passed in DTS (decode
189 * time stamp) order. Frames produced will always be in PTS (presentation
191 * If the decoder is configured with VPX_CODEC_USE_INPUT_FRAGMENTS enabled,
192 * data and data_sz can contain a fragment of the encoded frame. Fragment
193 * \#n must contain at least partition \#n, but can also contain subsequent
194 * partitions (\#n+1 - \#n+i), and if so, fragments \#n+1, .., \#n+i must
195 * be empty. When no more data is available, this function should be called
196 * with NULL as data and 0 as data_sz. The memory passed to this function
197 * must be available until the frame has been decoded.
199 * \param[in] ctx Pointer to this instance's context
200 * \param[in] data Pointer to this block of new coded data. If
201 * NULL, the put_frame callback is invoked for
202 * the previously decoded frame.
203 * \param[in] data_sz Size of the coded data, in bytes.
204 * \param[in] user_priv Application specific data to associate with
206 * \param[in] deadline Soft deadline the decoder should attempt to meet,
207 * in us. Set to zero for unlimited.
209 * \return Returns #VPX_CODEC_OK if the coded data was processed completely
210 * and future pictures can be decoded without error. Otherwise,
211 * see the descriptions of the other error codes in ::vpx_codec_err_t
212 * for recoverability capabilities.
214 vpx_codec_err_t vpx_codec_decode(vpx_codec_ctx_t *ctx, const uint8_t *data,
215 unsigned int data_sz, void *user_priv,
218 /*!\brief Decoded frames iterator
220 * Iterates over a list of the frames available for display. The iterator
221 * storage should be initialized to NULL to start the iteration. Iteration is
222 * complete when this function returns NULL.
224 * The list of available frames becomes valid upon completion of the
225 * vpx_codec_decode call, and remains valid until the next call to
228 * \param[in] ctx Pointer to this instance's context
229 * \param[in,out] iter Iterator storage, initialized to NULL
231 * \return Returns a pointer to an image, if one is ready for display. Frames
232 * produced will always be in PTS (presentation time stamp) order.
234 vpx_image_t *vpx_codec_get_frame(vpx_codec_ctx_t *ctx, vpx_codec_iter_t *iter);
236 /*!\defgroup cap_put_frame Frame-Based Decoding Functions
238 * The following function is required to be implemented for all decoders
239 * that advertise the VPX_CODEC_CAP_PUT_FRAME capability. Calling this
240 * function for codecs that don't advertise this capability will result in
241 * an error code being returned, usually VPX_CODEC_INCAPABLE.
245 /*!\brief put frame callback prototype
247 * This callback is invoked by the decoder to notify the application of
248 * the availability of decoded image data.
250 typedef void (*vpx_codec_put_frame_cb_fn_t)(void *user_priv,
251 const vpx_image_t *img);
253 /*!\brief Register for notification of frame completion.
255 * Registers a given function to be called when a decoded frame is
258 * \param[in] ctx Pointer to this instance's context
259 * \param[in] cb Pointer to the callback function
260 * \param[in] user_priv User's private data
262 * \retval #VPX_CODEC_OK
263 * Callback successfully registered.
264 * \retval #VPX_CODEC_ERROR
265 * Decoder context not initialized.
266 * \retval #VPX_CODEC_INCAPABLE
267 * Algorithm not capable of posting frame completion.
269 vpx_codec_err_t vpx_codec_register_put_frame_cb(vpx_codec_ctx_t *ctx,
270 vpx_codec_put_frame_cb_fn_t cb,
273 /*!@} - end defgroup cap_put_frame */
275 /*!\defgroup cap_put_slice Slice-Based Decoding Functions
277 * The following function is required to be implemented for all decoders
278 * that advertise the VPX_CODEC_CAP_PUT_SLICE capability. Calling this
279 * function for codecs that don't advertise this capability will result in
280 * an error code being returned, usually VPX_CODEC_INCAPABLE.
284 /*!\brief put slice callback prototype
286 * This callback is invoked by the decoder to notify the application of
287 * the availability of partially decoded image data.
289 typedef void (*vpx_codec_put_slice_cb_fn_t)(void *user_priv,
290 const vpx_image_t *img,
291 const vpx_image_rect_t *valid,
292 const vpx_image_rect_t *update);
294 /*!\brief Register for notification of slice completion.
296 * Registers a given function to be called when a decoded slice is
299 * \param[in] ctx Pointer to this instance's context
300 * \param[in] cb Pointer to the callback function
301 * \param[in] user_priv User's private data
303 * \retval #VPX_CODEC_OK
304 * Callback successfully registered.
305 * \retval #VPX_CODEC_ERROR
306 * Decoder context not initialized.
307 * \retval #VPX_CODEC_INCAPABLE
308 * Algorithm not capable of posting slice completion.
310 vpx_codec_err_t vpx_codec_register_put_slice_cb(vpx_codec_ctx_t *ctx,
311 vpx_codec_put_slice_cb_fn_t cb,
314 /*!@} - end defgroup cap_put_slice*/
316 /*!\defgroup cap_external_frame_buffer External Frame Buffer Functions
318 * The following function is required to be implemented for all decoders
319 * that advertise the VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER capability.
320 * Calling this function for codecs that don't advertise this capability
321 * will result in an error code being returned, usually VPX_CODEC_INCAPABLE.
324 * Currently this only works with VP9.
328 /*!\brief Pass in external frame buffers for the decoder to use.
330 * Registers functions to be called when libvpx needs a frame buffer
331 * to decode the current frame and a function to be called when libvpx does
332 * not internally reference the frame buffer. This set function must
333 * be called before the first call to decode or libvpx will assume the
334 * default behavior of allocating frame buffers internally.
336 * \param[in] ctx Pointer to this instance's context
337 * \param[in] cb_get Pointer to the get callback function
338 * \param[in] cb_release Pointer to the release callback function
339 * \param[in] cb_priv Callback's private data
341 * \retval #VPX_CODEC_OK
342 * External frame buffers will be used by libvpx.
343 * \retval #VPX_CODEC_INVALID_PARAM
344 * One or more of the callbacks were NULL.
345 * \retval #VPX_CODEC_ERROR
346 * Decoder context not initialized.
347 * \retval #VPX_CODEC_INCAPABLE
348 * Algorithm not capable of using external frame buffers.
351 * When decoding VP9, the application may be required to pass in at least
352 * #VP9_MAXIMUM_REF_BUFFERS + #VPX_MAXIMUM_WORK_BUFFERS external frame
355 vpx_codec_err_t vpx_codec_set_frame_buffer_functions(
356 vpx_codec_ctx_t *ctx, vpx_get_frame_buffer_cb_fn_t cb_get,
357 vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv);
359 /*!@} - end defgroup cap_external_frame_buffer */
361 /*!@} - end defgroup decoder*/
365 #endif // VPX_VPX_VPX_DECODER_H_