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 
11 
12 /*!\file
13  * \brief Describes the decoder algorithm interface for algorithm
14  *        implementations.
15  *
16  * This file defines the private structures and data types that are only
17  * relevant to implementing an algorithm, as opposed to using it.
18  *
19  * To create a decoder algorithm class, an interface structure is put
20  * into the global namespace:
21  *     <pre>
22  *     my_codec.c:
23  *       vpx_codec_iface_t my_codec = {
24  *           "My Codec v1.0",
25  *           VPX_CODEC_ALG_ABI_VERSION,
26  *           ...
27  *       };
28  *     </pre>
29  *
30  * An application instantiates a specific decoder instance by using
31  * vpx_codec_init() and a pointer to the algorithm's interface structure:
32  *     <pre>
33  *     my_app.c:
34  *       extern vpx_codec_iface_t my_codec;
35  *       {
36  *           vpx_codec_ctx_t algo;
37  *           res = vpx_codec_init(&algo, &my_codec);
38  *       }
39  *     </pre>
40  *
41  * Once initialized, the instance is manged using other functions from
42  * the vpx_codec_* family.
43  */
44 #ifndef VPX_INTERNAL_VPX_CODEC_INTERNAL_H_
45 #define VPX_INTERNAL_VPX_CODEC_INTERNAL_H_
46 #include "../vpx_decoder.h"
47 #include "../vpx_encoder.h"
48 #include <stdarg.h>
49 
50 #ifdef __cplusplus
51 extern "C" {
52 #endif
53 
54 /*!\brief Current ABI version number
55  *
56  * \internal
57  * If this file is altered in any way that changes the ABI, this value
58  * must be bumped.  Examples include, but are not limited to, changing
59  * types, removing or reassigning enums, adding/removing/rearranging
60  * fields to structures
61  */
62 #define VPX_CODEC_INTERNAL_ABI_VERSION (5) /**<\hideinitializer*/
63 
64 typedef struct vpx_codec_alg_priv  vpx_codec_alg_priv_t;
65 typedef struct vpx_codec_priv_enc_mr_cfg vpx_codec_priv_enc_mr_cfg_t;
66 
67 /*!\brief init function pointer prototype
68  *
69  * Performs algorithm-specific initialization of the decoder context. This
70  * function is called by the generic vpx_codec_init() wrapper function, so
71  * plugins implementing this interface may trust the input parameters to be
72  * properly initialized.
73  *
74  * \param[in] ctx   Pointer to this instance's context
75  * \retval #VPX_CODEC_OK
76  *     The input stream was recognized and decoder initialized.
77  * \retval #VPX_CODEC_MEM_ERROR
78  *     Memory operation failed.
79  */
80 typedef vpx_codec_err_t (*vpx_codec_init_fn_t)(vpx_codec_ctx_t *ctx,
81                                                vpx_codec_priv_enc_mr_cfg_t *data);
82 
83 /*!\brief destroy function pointer prototype
84  *
85  * Performs algorithm-specific destruction of the decoder context. This
86  * function is called by the generic vpx_codec_destroy() wrapper function,
87  * so plugins implementing this interface may trust the input parameters
88  * to be properly initialized.
89  *
90  * \param[in] ctx   Pointer to this instance's context
91  * \retval #VPX_CODEC_OK
92  *     The input stream was recognized and decoder initialized.
93  * \retval #VPX_CODEC_MEM_ERROR
94  *     Memory operation failed.
95  */
96 typedef vpx_codec_err_t (*vpx_codec_destroy_fn_t)(vpx_codec_alg_priv_t *ctx);
97 
98 /*!\brief parse stream info function pointer prototype
99  *
100  * Performs high level parsing of the bitstream. This function is called by the
101  * generic vpx_codec_peek_stream_info() wrapper function, so plugins
102  * implementing this interface may trust the input parameters to be properly
103  * initialized.
104  *
105  * \param[in]      data    Pointer to a block of data to parse
106  * \param[in]      data_sz Size of the data buffer
107  * \param[in,out]  si      Pointer to stream info to update. The size member
108  *                         \ref MUST be properly initialized, but \ref MAY be
109  *                         clobbered by the algorithm. This parameter \ref MAY
110  *                         be NULL.
111  *
112  * \retval #VPX_CODEC_OK
113  *     Bitstream is parsable and stream information updated
114  */
115 typedef vpx_codec_err_t (*vpx_codec_peek_si_fn_t)(const uint8_t         *data,
116                                                   unsigned int           data_sz,
117                                                   vpx_codec_stream_info_t *si);
118 
119 /*!\brief Return information about the current stream.
120  *
121  * Returns information about the stream that has been parsed during decoding.
122  *
123  * \param[in]      ctx     Pointer to this instance's context
124  * \param[in,out]  si      Pointer to stream info to update. The size member
125  *                         \ref MUST be properly initialized, but \ref MAY be
126  *                         clobbered by the algorithm. This parameter \ref MAY
127  *                         be NULL.
128  *
129  * \retval #VPX_CODEC_OK
130  *     Bitstream is parsable and stream information updated
131  */
132 typedef vpx_codec_err_t (*vpx_codec_get_si_fn_t)(vpx_codec_alg_priv_t    *ctx,
133                                                  vpx_codec_stream_info_t *si);
134 
135 /*!\brief control function pointer prototype
136  *
137  * This function is used to exchange algorithm specific data with the decoder
138  * instance. This can be used to implement features specific to a particular
139  * algorithm.
140  *
141  * This function is called by the generic vpx_codec_control() wrapper
142  * function, so plugins implementing this interface may trust the input
143  * parameters to be properly initialized. However,  this interface does not
144  * provide type safety for the exchanged data or assign meanings to the
145  * control codes. Those details should be specified in the algorithm's
146  * header file. In particular, the ctrl_id parameter is guaranteed to exist
147  * in the algorithm's control mapping table, and the data parameter may be NULL.
148  *
149  *
150  * \param[in]     ctx              Pointer to this instance's context
151  * \param[in]     ctrl_id          Algorithm specific control identifier
152  * \param[in,out] data             Data to exchange with algorithm instance.
153  *
154  * \retval #VPX_CODEC_OK
155  *     The internal state data was deserialized.
156  */
157 typedef vpx_codec_err_t (*vpx_codec_control_fn_t)(vpx_codec_alg_priv_t  *ctx,
158                                                   int                  ctrl_id,
159                                                   va_list              ap);
160 
161 /*!\brief control function pointer mapping
162  *
163  * This structure stores the mapping between control identifiers and
164  * implementing functions. Each algorithm provides a list of these
165  * mappings. This list is searched by the vpx_codec_control() wrapper
166  * function to determine which function to invoke. The special
167  * value {0, NULL} is used to indicate end-of-list, and must be
168  * present. The special value {0, <non-null>} can be used as a catch-all
169  * mapping. This implies that ctrl_id values chosen by the algorithm
170  * \ref MUST be non-zero.
171  */
172 typedef const struct vpx_codec_ctrl_fn_map {
173   int                    ctrl_id;
174   vpx_codec_control_fn_t   fn;
175 } vpx_codec_ctrl_fn_map_t;
176 
177 /*!\brief decode data function pointer prototype
178  *
179  * Processes a buffer of coded data. If the processing results in a new
180  * decoded frame becoming available, #VPX_CODEC_CB_PUT_SLICE and
181  * #VPX_CODEC_CB_PUT_FRAME events are generated as appropriate. This
182  * function is called by the generic vpx_codec_decode() wrapper function,
183  * so plugins implementing this interface may trust the input parameters
184  * to be properly initialized.
185  *
186  * \param[in] ctx          Pointer to this instance's context
187  * \param[in] data         Pointer to this block of new coded data. If
188  *                         NULL, a #VPX_CODEC_CB_PUT_FRAME event is posted
189  *                         for the previously decoded frame.
190  * \param[in] data_sz      Size of the coded data, in bytes.
191  *
192  * \return Returns #VPX_CODEC_OK if the coded data was processed completely
193  *         and future pictures can be decoded without error. Otherwise,
194  *         see the descriptions of the other error codes in ::vpx_codec_err_t
195  *         for recoverability capabilities.
196  */
197 typedef vpx_codec_err_t (*vpx_codec_decode_fn_t)(vpx_codec_alg_priv_t  *ctx,
198                                                  const uint8_t         *data,
199                                                  unsigned int     data_sz,
200                                                  void        *user_priv,
201                                                  long         deadline);
202 
203 /*!\brief Decoded frames iterator
204  *
205  * Iterates over a list of the frames available for display. The iterator
206  * storage should be initialized to NULL to start the iteration. Iteration is
207  * complete when this function returns NULL.
208  *
209  * The list of available frames becomes valid upon completion of the
210  * vpx_codec_decode call, and remains valid until the next call to vpx_codec_decode.
211  *
212  * \param[in]     ctx      Pointer to this instance's context
213  * \param[in out] iter     Iterator storage, initialized to NULL
214  *
215  * \return Returns a pointer to an image, if one is ready for display. Frames
216  *         produced will always be in PTS (presentation time stamp) order.
217  */
218 typedef vpx_image_t *(*vpx_codec_get_frame_fn_t)(vpx_codec_alg_priv_t *ctx,
219                                                  vpx_codec_iter_t     *iter);
220 
221 /*!\brief Pass in external frame buffers for the decoder to use.
222  *
223  * Registers functions to be called when libvpx needs a frame buffer
224  * to decode the current frame and a function to be called when libvpx does
225  * not internally reference the frame buffer. This set function must
226  * be called before the first call to decode or libvpx will assume the
227  * default behavior of allocating frame buffers internally.
228  *
229  * \param[in] ctx          Pointer to this instance's context
230  * \param[in] cb_get       Pointer to the get callback function
231  * \param[in] cb_release   Pointer to the release callback function
232  * \param[in] cb_priv      Callback's private data
233  *
234  * \retval #VPX_CODEC_OK
235  *     External frame buffers will be used by libvpx.
236  * \retval #VPX_CODEC_INVALID_PARAM
237  *     One or more of the callbacks were NULL.
238  * \retval #VPX_CODEC_ERROR
239  *     Decoder context not initialized, or algorithm not capable of
240  *     using external frame buffers.
241  *
242  * \note
243  * When decoding VP9, the application may be required to pass in at least
244  * #VP9_MAXIMUM_REF_BUFFERS + #VPX_MAXIMUM_WORK_BUFFERS external frame
245  * buffers.
246  */
247 typedef vpx_codec_err_t (*vpx_codec_set_fb_fn_t)(
248     vpx_codec_alg_priv_t *ctx,
249     vpx_get_frame_buffer_cb_fn_t cb_get,
250     vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv);
251 
252 /*\brief eXternal Memory Allocation memory map get iterator
253  *
254  * Iterates over a list of the memory maps requested by the decoder. The
255  * iterator storage should be initialized to NULL to start the iteration.
256  * Iteration is complete when this function returns NULL.
257  *
258  * \param[in out] iter     Iterator storage, initialized to NULL
259  *
260  * \return Returns a pointer to an memory segment descriptor, or NULL to
261  *         indicate end-of-list.
262  */
263 typedef vpx_codec_err_t (*vpx_codec_get_mmap_fn_t)(const vpx_codec_ctx_t      *ctx,
264                                                    vpx_codec_mmap_t           *mmap,
265                                                    vpx_codec_iter_t           *iter);
266 
267 
268 /*\brief eXternal Memory Allocation memory map set iterator
269  *
270  * Sets a memory descriptor inside the decoder instance.
271  *
272  * \param[in] ctx      Pointer to this instance's context
273  * \param[in] mmap     Memory map to store.
274  *
275  * \retval #VPX_CODEC_OK
276  *     The memory map was accepted and stored.
277  * \retval #VPX_CODEC_MEM_ERROR
278  *     The memory map was rejected.
279  */
280 typedef vpx_codec_err_t (*vpx_codec_set_mmap_fn_t)(vpx_codec_ctx_t         *ctx,
281                                                    const vpx_codec_mmap_t  *mmap);
282 
283 
284 typedef vpx_codec_err_t (*vpx_codec_encode_fn_t)(vpx_codec_alg_priv_t  *ctx,
285                                                  const vpx_image_t     *img,
286                                                  vpx_codec_pts_t        pts,
287                                                  unsigned long          duration,
288                                                  vpx_enc_frame_flags_t  flags,
289                                                  unsigned long          deadline);
290 typedef const vpx_codec_cx_pkt_t *(*vpx_codec_get_cx_data_fn_t)(vpx_codec_alg_priv_t *ctx,
291                                                                 vpx_codec_iter_t     *iter);
292 
293 typedef vpx_codec_err_t
294 (*vpx_codec_enc_config_set_fn_t)(vpx_codec_alg_priv_t       *ctx,
295                                  const vpx_codec_enc_cfg_t  *cfg);
296 typedef vpx_fixed_buf_t *
297 (*vpx_codec_get_global_headers_fn_t)(vpx_codec_alg_priv_t   *ctx);
298 
299 typedef vpx_image_t *
300 (*vpx_codec_get_preview_frame_fn_t)(vpx_codec_alg_priv_t   *ctx);
301 
302 typedef vpx_codec_err_t
303 (*vpx_codec_enc_mr_get_mem_loc_fn_t)(const vpx_codec_enc_cfg_t     *cfg,
304                                      void **mem_loc);
305 
306 /*!\brief usage configuration mapping
307  *
308  * This structure stores the mapping between usage identifiers and
309  * configuration structures. Each algorithm provides a list of these
310  * mappings. This list is searched by the vpx_codec_enc_config_default()
311  * wrapper function to determine which config to return. The special value
312  * {-1, {0}} is used to indicate end-of-list, and must be present. At least
313  * one mapping must be present, in addition to the end-of-list.
314  *
315  */
316 typedef const struct vpx_codec_enc_cfg_map {
317   int                 usage;
318   vpx_codec_enc_cfg_t cfg;
319 } vpx_codec_enc_cfg_map_t;
320 
321 #define NOT_IMPLEMENTED 0
322 
323 /*!\brief Decoder algorithm interface interface
324  *
325  * All decoders \ref MUST expose a variable of this type.
326  */
327 struct vpx_codec_iface {
328   const char               *name;        /**< Identification String  */
329   int                       abi_version; /**< Implemented ABI version */
330   vpx_codec_caps_t          caps;    /**< Decoder capabilities */
331   vpx_codec_init_fn_t       init;    /**< \copydoc ::vpx_codec_init_fn_t */
332   vpx_codec_destroy_fn_t    destroy;     /**< \copydoc ::vpx_codec_destroy_fn_t */
333   vpx_codec_ctrl_fn_map_t  *ctrl_maps;   /**< \copydoc ::vpx_codec_ctrl_fn_map_t */
334   vpx_codec_get_mmap_fn_t   get_mmap;    /**< \copydoc ::vpx_codec_get_mmap_fn_t */
335   vpx_codec_set_mmap_fn_t   set_mmap;    /**< \copydoc ::vpx_codec_set_mmap_fn_t */
336   struct vpx_codec_dec_iface {
337     vpx_codec_peek_si_fn_t    peek_si;     /**< \copydoc ::vpx_codec_peek_si_fn_t */
338     vpx_codec_get_si_fn_t     get_si;      /**< \copydoc ::vpx_codec_get_si_fn_t */
339     vpx_codec_decode_fn_t     decode;      /**< \copydoc ::vpx_codec_decode_fn_t */
340     vpx_codec_get_frame_fn_t  get_frame;   /**< \copydoc ::vpx_codec_get_frame_fn_t */
341     vpx_codec_set_fb_fn_t     set_fb_fn;   /**< \copydoc ::vpx_codec_set_fb_fn_t */
342   } dec;
343   struct vpx_codec_enc_iface {
344     vpx_codec_enc_cfg_map_t           *cfg_maps;      /**< \copydoc ::vpx_codec_enc_cfg_map_t */
345     vpx_codec_encode_fn_t              encode;        /**< \copydoc ::vpx_codec_encode_fn_t */
346     vpx_codec_get_cx_data_fn_t         get_cx_data;   /**< \copydoc ::vpx_codec_get_cx_data_fn_t */
347     vpx_codec_enc_config_set_fn_t      cfg_set;       /**< \copydoc ::vpx_codec_enc_config_set_fn_t */
348     vpx_codec_get_global_headers_fn_t  get_glob_hdrs; /**< \copydoc ::vpx_codec_get_global_headers_fn_t */
349     vpx_codec_get_preview_frame_fn_t   get_preview;   /**< \copydoc ::vpx_codec_get_preview_frame_fn_t */
350     vpx_codec_enc_mr_get_mem_loc_fn_t  mr_get_mem_loc;   /**< \copydoc ::vpx_codec_enc_mr_get_mem_loc_fn_t */
351   } enc;
352 };
353 
354 /*!\brief Callback function pointer / user data pair storage */
355 typedef struct vpx_codec_priv_cb_pair {
356   union {
357     vpx_codec_put_frame_cb_fn_t    put_frame;
358     vpx_codec_put_slice_cb_fn_t    put_slice;
359   } u;
360   void                            *user_priv;
361 } vpx_codec_priv_cb_pair_t;
362 
363 
364 /*!\brief Instance private storage
365  *
366  * This structure is allocated by the algorithm's init function. It can be
367  * extended in one of two ways. First, a second, algorithm specific structure
368  * can be allocated and the priv member pointed to it. Alternatively, this
369  * structure can be made the first member of the algorithm specific structure,
370  * and the pointer cast to the proper type.
371  */
372 struct vpx_codec_priv {
373   unsigned int                    sz;
374   vpx_codec_iface_t              *iface;
375   struct vpx_codec_alg_priv      *alg_priv;
376   const char                     *err_detail;
377   vpx_codec_flags_t               init_flags;
378   struct {
379     vpx_codec_priv_cb_pair_t    put_frame_cb;
380     vpx_codec_priv_cb_pair_t    put_slice_cb;
381   } dec;
382   struct {
383     int                         tbd;
384     struct vpx_fixed_buf        cx_data_dst_buf;
385     unsigned int                cx_data_pad_before;
386     unsigned int                cx_data_pad_after;
387     vpx_codec_cx_pkt_t          cx_data_pkt;
388     unsigned int                total_encoders;
389   } enc;
390 };
391 
392 /*
393  * Multi-resolution encoding internal configuration
394  */
395 struct vpx_codec_priv_enc_mr_cfg
396 {
397     unsigned int           mr_total_resolutions;
398     unsigned int           mr_encoder_id;
399     struct vpx_rational    mr_down_sampling_factor;
400     void*                  mr_low_res_mode_info;
401 };
402 
403 #undef VPX_CTRL_USE_TYPE
404 #define VPX_CTRL_USE_TYPE(id, typ) \
405   static typ id##__value(va_list args) {return va_arg(args, typ);} \
406   static typ id##__convert(void *x)\
407   {\
408     union\
409     {\
410       void *x;\
411       typ   d;\
412     } u;\
413     u.x = x;\
414     return u.d;\
415   }
416 
417 
418 #undef VPX_CTRL_USE_TYPE_DEPRECATED
419 #define VPX_CTRL_USE_TYPE_DEPRECATED(id, typ) \
420   static typ id##__value(va_list args) {return va_arg(args, typ);} \
421   static typ id##__convert(void *x)\
422   {\
423     union\
424     {\
425       void *x;\
426       typ   d;\
427     } u;\
428     u.x = x;\
429     return u.d;\
430   }
431 
432 #define CAST(id, arg) id##__value(arg)
433 #define RECAST(id, x) id##__convert(x)
434 
435 
436 /* CODEC_INTERFACE convenience macro
437  *
438  * By convention, each codec interface is a struct with extern linkage, where
439  * the symbol is suffixed with _algo. A getter function is also defined to
440  * return a pointer to the struct, since in some cases it's easier to work
441  * with text symbols than data symbols (see issue #169). This function has
442  * the same name as the struct, less the _algo suffix. The CODEC_INTERFACE
443  * macro is provided to define this getter function automatically.
444  */
445 #define CODEC_INTERFACE(id)\
446   vpx_codec_iface_t* id(void) { return &id##_algo; }\
447   vpx_codec_iface_t  id##_algo
448 
449 
450 /* Internal Utility Functions
451  *
452  * The following functions are intended to be used inside algorithms as
453  * utilities for manipulating vpx_codec_* data structures.
454  */
455 struct vpx_codec_pkt_list {
456   unsigned int            cnt;
457   unsigned int            max;
458   struct vpx_codec_cx_pkt pkts[1];
459 };
460 
461 #define vpx_codec_pkt_list_decl(n)\
462   union {struct vpx_codec_pkt_list head;\
463     struct {struct vpx_codec_pkt_list head;\
464       struct vpx_codec_cx_pkt    pkts[n];} alloc;}
465 
466 #define vpx_codec_pkt_list_init(m)\
467   (m)->alloc.head.cnt = 0,\
468                         (m)->alloc.head.max = sizeof((m)->alloc.pkts) / sizeof((m)->alloc.pkts[0])
469 
470 int
471 vpx_codec_pkt_list_add(struct vpx_codec_pkt_list *,
472                        const struct vpx_codec_cx_pkt *);
473 
474 const vpx_codec_cx_pkt_t *
475 vpx_codec_pkt_list_get(struct vpx_codec_pkt_list *list,
476                        vpx_codec_iter_t           *iter);
477 
478 
479 #include <stdio.h>
480 #include <setjmp.h>
481 
482 struct vpx_internal_error_info {
483   vpx_codec_err_t  error_code;
484   int              has_detail;
485   char             detail[80];
486   int              setjmp;
487   jmp_buf          jmp;
488 };
489 
vpx_internal_error(struct vpx_internal_error_info * info,vpx_codec_err_t error,const char * fmt,...)490 static void vpx_internal_error(struct vpx_internal_error_info *info,
491                                vpx_codec_err_t                 error,
492                                const char                     *fmt,
493                                ...) {
494   va_list ap;
495 
496   info->error_code = error;
497   info->has_detail = 0;
498 
499   if (fmt) {
500     size_t  sz = sizeof(info->detail);
501 
502     info->has_detail = 1;
503     va_start(ap, fmt);
504     vsnprintf(info->detail, sz - 1, fmt, ap);
505     va_end(ap);
506     info->detail[sz - 1] = '\0';
507   }
508 
509   if (info->setjmp)
510     longjmp(info->jmp, info->error_code);
511 }
512 
513 //------------------------------------------------------------------------------
514 // mmap interface
515 
516 typedef struct {
517   unsigned int   id;
518   unsigned long  sz;
519   unsigned int   align;
520   unsigned int   flags;
521   unsigned long (*calc_sz)(const vpx_codec_dec_cfg_t *, vpx_codec_flags_t);
522 } mem_req_t;
523 
524 // Allocates mmap.priv and sets mmap.base based on mmap.sz/align/flags
525 // requirements.
526 // Returns #VPX_CODEC_OK on success, #VPX_CODEC_MEM_ERROR otherwise.
527 vpx_codec_err_t vpx_mmap_alloc(vpx_codec_mmap_t *mmap);
528 
529 // Frees mmap.base allocated by a call to vpx_mmap_alloc().
530 void vpx_mmap_dtor(vpx_codec_mmap_t *mmap);
531 
532 // Checks each mmap has the size requirement specificied by mem_reqs.
533 // Returns #VPX_CODEC_OK on success, #VPX_CODEC_MEM_ERROR otherwise.
534 vpx_codec_err_t vpx_validate_mmaps(const vpx_codec_stream_info_t *si,
535                                    const vpx_codec_mmap_t *mmaps,
536                                    const mem_req_t *mem_reqs, int nreqs,
537                                    vpx_codec_flags_t init_flags);
538 #ifdef __cplusplus
539 }  // extern "C"
540 #endif
541 
542 #endif  // VPX_INTERNAL_VPX_CODEC_INTERNAL_H_
543