1 /*
2 * This file is part of FFmpeg.
3 *
4 * FFmpeg is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Lesser General Public
6 * License as published by the Free Software Foundation; either
7 * version 2.1 of the License, or (at your option) any later version.
8 *
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Lesser General Public License for more details.
13 *
14 * You should have received a copy of the GNU Lesser General Public
15 * License along with FFmpeg; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17 */
18
19 #ifndef AVCODEC_CODEC_INTERNAL_H
20 #define AVCODEC_CODEC_INTERNAL_H
21
22 #include <stdint.h>
23
24 #include "libavutil/attributes.h"
25 #include "codec.h"
26
27 /**
28 * The codec does not modify any global variables in the init function,
29 * allowing to call the init function without locking any global mutexes.
30 */
31 #define FF_CODEC_CAP_INIT_THREADSAFE (1 << 0)
32 /**
33 * The codec allows calling the close function for deallocation even if
34 * the init function returned a failure. Without this capability flag, a
35 * codec does such cleanup internally when returning failures from the
36 * init function and does not expect the close function to be called at
37 * all.
38 */
39 #define FF_CODEC_CAP_INIT_CLEANUP (1 << 1)
40 /**
41 * Decoders marked with FF_CODEC_CAP_SETS_PKT_DTS want to set
42 * AVFrame.pkt_dts manually. If the flag is set, decode.c won't overwrite
43 * this field. If it's unset, decode.c tries to guess the pkt_dts field
44 * from the input AVPacket.
45 */
46 #define FF_CODEC_CAP_SETS_PKT_DTS (1 << 2)
47 /**
48 * The decoder extracts and fills its parameters even if the frame is
49 * skipped due to the skip_frame setting.
50 */
51 #define FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM (1 << 3)
52 /**
53 * The decoder sets the cropping fields in the output frames manually.
54 * If this cap is set, the generic code will initialize output frame
55 * dimensions to coded rather than display values.
56 */
57 #define FF_CODEC_CAP_EXPORTS_CROPPING (1 << 4)
58 /**
59 * Codec initializes slice-based threading with a main function
60 */
61 #define FF_CODEC_CAP_SLICE_THREAD_HAS_MF (1 << 5)
62 /*
63 * The codec supports frame threading and has inter-frame dependencies, so it
64 * uses ff_thread_report/await_progress().
65 */
66 #define FF_CODEC_CAP_ALLOCATE_PROGRESS (1 << 6)
67 /**
68 * Codec handles avctx->thread_count == 0 (auto) internally.
69 */
70 #define FF_CODEC_CAP_AUTO_THREADS (1 << 7)
71 /**
72 * Codec handles output frame properties internally instead of letting the
73 * internal logic derive them from AVCodecInternal.last_pkt_props.
74 */
75 #define FF_CODEC_CAP_SETS_FRAME_PROPS (1 << 8)
76
77 /**
78 * FFCodec.codec_tags termination value
79 */
80 #define FF_CODEC_TAGS_END -1
81
82 typedef struct FFCodecDefault {
83 const char *key;
84 const char *value;
85 } FFCodecDefault;
86
87 struct AVCodecContext;
88 struct AVSubtitle;
89 struct AVPacket;
90
91 enum FFCodecType {
92 /* The codec is a decoder using the decode callback;
93 * audio and video codecs only. */
94 FF_CODEC_CB_TYPE_DECODE,
95 /* The codec is a decoder using the decode_sub callback;
96 * subtitle codecs only. */
97 FF_CODEC_CB_TYPE_DECODE_SUB,
98 /* The codec is a decoder using the receive_frame callback;
99 * audio and video codecs only. */
100 FF_CODEC_CB_TYPE_RECEIVE_FRAME,
101 /* The codec is an encoder using the encode callback;
102 * audio and video codecs only. */
103 FF_CODEC_CB_TYPE_ENCODE,
104 /* The codec is an encoder using the encode_sub callback;
105 * subtitle codecs only. */
106 FF_CODEC_CB_TYPE_ENCODE_SUB,
107 /* The codec is an encoder using the receive_packet callback;
108 * audio and video codecs only. */
109 FF_CODEC_CB_TYPE_RECEIVE_PACKET,
110 };
111
112 typedef struct FFCodec {
113 /**
114 * The public AVCodec. See codec.h for it.
115 */
116 AVCodec p;
117
118 /**
119 * Internal codec capabilities FF_CODEC_CAP_*.
120 */
121 unsigned caps_internal:29;
122
123 /**
124 * This field determines the type of the codec (decoder/encoder)
125 * and also the exact callback cb implemented by the codec.
126 * cb_type uses enum FFCodecType values.
127 */
128 unsigned cb_type:3;
129
130 int priv_data_size;
131 /**
132 * @name Frame-level threading support functions
133 * @{
134 */
135 /**
136 * Copy necessary context variables from a previous thread context to the current one.
137 * If not defined, the next thread will start automatically; otherwise, the codec
138 * must call ff_thread_finish_setup().
139 *
140 * dst and src will (rarely) point to the same context, in which case memcpy should be skipped.
141 */
142 int (*update_thread_context)(struct AVCodecContext *dst, const struct AVCodecContext *src);
143
144 /**
145 * Copy variables back to the user-facing context
146 */
147 int (*update_thread_context_for_user)(struct AVCodecContext *dst, const struct AVCodecContext *src);
148 /** @} */
149
150 /**
151 * Private codec-specific defaults.
152 */
153 const FFCodecDefault *defaults;
154
155 /**
156 * Initialize codec static data, called from av_codec_iterate().
157 *
158 * This is not intended for time consuming operations as it is
159 * run for every codec regardless of that codec being used.
160 */
161 void (*init_static_data)(struct FFCodec *codec);
162
163 int (*init)(struct AVCodecContext *);
164
165 union {
166 /**
167 * Decode to an AVFrame.
168 * cb is in this state if cb_type is FF_CODEC_CB_TYPE_DECODE.
169 *
170 * @param avctx codec context
171 * @param[out] frame AVFrame for output
172 * @param[out] got_frame_ptr decoder sets to 0 or 1 to indicate that
173 * a non-empty frame was returned in frame.
174 * @param[in] avpkt AVPacket containing the data to be decoded
175 * @return amount of bytes read from the packet on success,
176 * negative error code on failure
177 */
178 int (*decode)(struct AVCodecContext *avctx, struct AVFrame *frame,
179 int *got_frame_ptr, struct AVPacket *avpkt);
180 /**
181 * Decode subtitle data to an AVSubtitle.
182 * cb is in this state if cb_type is FF_CODEC_CB_TYPE_DECODE_SUB.
183 *
184 * Apart from that this is like the decode callback.
185 */
186 int (*decode_sub)(struct AVCodecContext *avctx, struct AVSubtitle *sub,
187 int *got_frame_ptr, const struct AVPacket *avpkt);
188 /**
189 * Decode API with decoupled packet/frame dataflow.
190 * cb is in this state if cb_type is FF_CODEC_CB_TYPE_RECEIVE_FRAME.
191 *
192 * This function is called to get one output frame. It should call
193 * ff_decode_get_packet() to obtain input data.
194 */
195 int (*receive_frame)(struct AVCodecContext *avctx, struct AVFrame *frame);
196 /**
197 * Encode data to an AVPacket.
198 * cb is in this state if cb_type is FF_CODEC_CB_TYPE_ENCODE
199 *
200 * @param avctx codec context
201 * @param[out] avpkt output AVPacket
202 * @param[in] frame AVFrame containing the input to be encoded
203 * @param[out] got_packet_ptr encoder sets to 0 or 1 to indicate that a
204 * non-empty packet was returned in avpkt.
205 * @return 0 on success, negative error code on failure
206 */
207 int (*encode)(struct AVCodecContext *avctx, struct AVPacket *avpkt,
208 const struct AVFrame *frame, int *got_packet_ptr);
209 /**
210 * Encode subtitles to a raw buffer.
211 * cb is in this state if cb_type is FF_CODEC_CB_TYPE_ENCODE_SUB.
212 */
213 int (*encode_sub)(struct AVCodecContext *avctx, uint8_t *buf,
214 int buf_size, const struct AVSubtitle *sub);
215 /**
216 * Encode API with decoupled frame/packet dataflow.
217 * cb is in this state if cb_type is FF_CODEC_CB_TYPE_RECEIVE_PACKET.
218 *
219 * This function is called to get one output packet.
220 * It should call ff_encode_get_frame() to obtain input data.
221 */
222 int (*receive_packet)(struct AVCodecContext *avctx, struct AVPacket *avpkt);
223 } cb;
224
225 int (*close)(struct AVCodecContext *);
226
227 /**
228 * Flush buffers.
229 * Will be called when seeking
230 */
231 void (*flush)(struct AVCodecContext *);
232
233 /**
234 * Decoding only, a comma-separated list of bitstream filters to apply to
235 * packets before decoding.
236 */
237 const char *bsfs;
238
239 /**
240 * Array of pointers to hardware configurations supported by the codec,
241 * or NULL if no hardware supported. The array is terminated by a NULL
242 * pointer.
243 *
244 * The user can only access this field via avcodec_get_hw_config().
245 */
246 const struct AVCodecHWConfigInternal *const *hw_configs;
247
248 /**
249 * List of supported codec_tags, terminated by FF_CODEC_TAGS_END.
250 */
251 const uint32_t *codec_tags;
252 } FFCodec;
253
254 #define FF_CODEC_DECODE_CB(func) \
255 .cb_type = FF_CODEC_CB_TYPE_DECODE, \
256 .cb.decode = (func)
257 #define FF_CODEC_DECODE_SUB_CB(func) \
258 .cb_type = FF_CODEC_CB_TYPE_DECODE_SUB, \
259 .cb.decode_sub = (func)
260 #define FF_CODEC_RECEIVE_FRAME_CB(func) \
261 .cb_type = FF_CODEC_CB_TYPE_RECEIVE_FRAME, \
262 .cb.receive_frame = (func)
263 #define FF_CODEC_ENCODE_CB(func) \
264 .cb_type = FF_CODEC_CB_TYPE_ENCODE, \
265 .cb.encode = (func)
266 #define FF_CODEC_ENCODE_SUB_CB(func) \
267 .cb_type = FF_CODEC_CB_TYPE_ENCODE_SUB, \
268 .cb.encode_sub = (func)
269 #define FF_CODEC_RECEIVE_PACKET_CB(func) \
270 .cb_type = FF_CODEC_CB_TYPE_RECEIVE_PACKET, \
271 .cb.receive_packet = (func)
272
ffcodec(const AVCodec *codec)273 static av_always_inline const FFCodec *ffcodec(const AVCodec *codec)
274 {
275 return (const FFCodec*)codec;
276 }
277
278 #endif /* AVCODEC_CODEC_INTERNAL_H */
279