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internal.h
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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 /**
20  * @file
21  * common internal api header.
22  */
23 
24 #ifndef AVCODEC_INTERNAL_H
25 #define AVCODEC_INTERNAL_H
26 
27 #include <stdint.h>
28 
29 #include "libavutil/buffer.h"
31 #include "libavutil/mathematics.h"
32 #include "libavutil/pixfmt.h"
33 #include "avcodec.h"
34 #include "config.h"
35 
36 #define FF_SANE_NB_CHANNELS 63U
37 
38 #if HAVE_NEON || ARCH_PPC || HAVE_MMX
39 # define STRIDE_ALIGN 16
40 #else
41 # define STRIDE_ALIGN 8
42 #endif
43 
44 typedef struct FramePool {
45  /**
46  * Pools for each data plane. For audio all the planes have the same size,
47  * so only pools[0] is used.
48  */
50 
51  /*
52  * Pool parameters
53  */
54  int format;
55  int width, height;
57  int linesize[4];
58  int planes;
59  int channels;
60  int samples;
61 } FramePool;
62 
63 typedef struct AVCodecInternal {
64  /**
65  * Whether the parent AVCodecContext is a copy of the context which had
66  * init() called on it.
67  * This is used by multithreading - shared tables and picture pointers
68  * should be freed from the original context only.
69  */
70  int is_copy;
71 
72  /**
73  * Whether to allocate progress for frame threading.
74  *
75  * The codec must set it to 1 if it uses ff_thread_await/report_progress(),
76  * then progress will be allocated in ff_thread_get_buffer(). The frames
77  * then MUST be freed with ff_thread_release_buffer().
78  *
79  * If the codec does not need to call the progress functions (there are no
80  * dependencies between the frames), it should leave this at 0. Then it can
81  * decode straight to the user-provided frames (which the user will then
82  * free with av_frame_unref()), there is no need to call
83  * ff_thread_release_buffer().
84  */
86 
87 #if FF_API_OLD_ENCODE_AUDIO
88  /**
89  * Internal sample count used by avcodec_encode_audio() to fabricate pts.
90  * Can be removed along with avcodec_encode_audio().
91  */
92  int64_t sample_count;
93 #endif
94 
95  /**
96  * An audio frame with less than required samples has been submitted and
97  * padded with silence. Reject all subsequent frames.
98  */
100 
102 
104 
105  void *thread_ctx;
106 
107  /**
108  * Current packet as passed into the decoder, to avoid having to pass the
109  * packet into every function.
110  */
112 
113  /**
114  * temporary buffer used for encoders to store their bitstream
115  */
117  unsigned int byte_buffer_size;
118 
120 
121  /**
122  * Number of audio samples to skip at the start of the next decoded frame
123  */
126 
128  const uint8_t *key;
129  const uint8_t *value;
130 };
131 
132 /**
133  * Return the hardware accelerated codec for codec codec_id and
134  * pixel format pix_fmt.
135  *
136  * @param avctx The codec context containing the codec_id and pixel format.
137  * @return the hardware accelerated codec, or NULL if none was found.
138  */
140 
141 /**
142  * Return the index into tab at which {a,b} match elements {[0],[1]} of tab.
143  * If there is no such matching pair then size is returned.
144  */
145 int ff_match_2uint16(const uint16_t (*tab)[2], int size, int a, int b);
146 
147 unsigned int avpriv_toupper4(unsigned int x);
148 
149 /**
150  * does needed setup of pkt_pts/pos and such for (re)get_buffer();
151  */
153 
154 
155 void avpriv_color_frame(AVFrame *frame, const int color[4]);
156 
157 extern volatile int ff_avcodec_locked;
158 int ff_lock_avcodec(AVCodecContext *log_ctx);
159 int ff_unlock_avcodec(void);
160 
161 int avpriv_lock_avformat(void);
162 int avpriv_unlock_avformat(void);
163 
164 /**
165  * Maximum size in bytes of extradata.
166  * This value was chosen such that every bit of the buffer is
167  * addressable by a 32-bit signed integer as used by get_bits.
168  */
169 #define FF_MAX_EXTRADATA_SIZE ((1 << 28) - FF_INPUT_BUFFER_PADDING_SIZE)
170 
171 /**
172  * Check AVPacket size and/or allocate data.
173  *
174  * Encoders supporting AVCodec.encode2() can use this as a convenience to
175  * ensure the output packet data is large enough, whether provided by the user
176  * or allocated in this function.
177  *
178  * @param avctx the AVCodecContext of the encoder
179  * @param avpkt the AVPacket
180  * If avpkt->data is already set, avpkt->size is checked
181  * to ensure it is large enough.
182  * If avpkt->data is NULL, a new buffer is allocated.
183  * avpkt->size is set to the specified size.
184  * All other AVPacket fields will be reset with av_init_packet().
185  * @param size the minimum required packet size
186  * @return 0 on success, negative error code on failure
187  */
188 int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size);
189 
190 int ff_alloc_packet(AVPacket *avpkt, int size);
191 
192 /**
193  * Rescale from sample rate to AVCodecContext.time_base.
194  */
196  int64_t samples)
197 {
198  if(samples == AV_NOPTS_VALUE)
199  return AV_NOPTS_VALUE;
200  return av_rescale_q(samples, (AVRational){ 1, avctx->sample_rate },
201  avctx->time_base);
202 }
203 
204 /**
205  * Get a buffer for a frame. This is a wrapper around
206  * AVCodecContext.get_buffer() and should be used instead calling get_buffer()
207  * directly.
208  */
209 int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags);
210 
211 /**
212  * Identical in function to av_frame_make_writable(), except it uses
213  * ff_get_buffer() to allocate the buffer when needed.
214  */
216 
218 
220 
221 /**
222  * Call avcodec_open2 recursively by decrementing counter, unlocking mutex,
223  * calling the function and then restoring again. Assumes the mutex is
224  * already locked
225  */
227 
228 /**
229  * Call avcodec_close recursively, counterpart to avcodec_open2_recursive.
230  */
232 
233 /**
234  * Finalize buf into extradata and set its size appropriately.
235  */
237 
238 const uint8_t *avpriv_find_start_code(const uint8_t *p,
239  const uint8_t *end,
240  uint32_t *state);
241 
242 /**
243  * Check that the provided frame dimensions are valid and set them on the codec
244  * context.
245  */
247 
248 /**
249  * Add or update AV_FRAME_DATA_MATRIXENCODING side data.
250  */
252  enum AVMatrixEncoding matrix_encoding);
253 
254 #endif /* AVCODEC_INTERNAL_H */