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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/mathematics.h"
30 #include "libavutil/pixfmt.h"
31 #include "avcodec.h"
32 
33 #define FF_SANE_NB_CHANNELS 128U
34 
35 typedef struct InternalBuffer {
39  int width;
40  int height;
43 
44 typedef struct AVCodecInternal {
45  /**
46  * internal buffer count
47  * used by default get/release/reget_buffer().
48  */
50 
51  /**
52  * internal buffers
53  * used by default get/release/reget_buffer().
54  */
56 
57  /**
58  * Whether the parent AVCodecContext is a copy of the context which had
59  * init() called on it.
60  * This is used by multithreading - shared tables and picture pointers
61  * should be freed from the original context only.
62  */
63  int is_copy;
64 
65 #if FF_API_OLD_DECODE_AUDIO
66  /**
67  * Internal sample count used by avcodec_encode_audio() to fabricate pts.
68  * Can be removed along with avcodec_encode_audio().
69  */
70  int sample_count;
71 #endif
72 
73  /**
74  * An audio frame with less than required samples has been submitted and
75  * padded with silence. Reject all subsequent frames.
76  */
78 
79  /**
80  * The data for the last allocated audio frame.
81  * Stored here so we can free it.
82  */
84 
85  /**
86  * temporary buffer used for encoders to store their bitstream
87  */
89  unsigned int byte_buffer_size;
90 
92 
93  /**
94  * Number of audio samples to skip at the start of the next decoded frame
95  */
98 
100  const uint8_t *key;
101  const uint8_t *value;
102 };
103 
104 /**
105  * Return the hardware accelerated codec for codec codec_id and
106  * pixel format pix_fmt.
107  *
108  * @param codec_id the codec to match
109  * @param pix_fmt the pixel format to match
110  * @return the hardware accelerated codec, or NULL if none was found.
111  */
113 
114 /**
115  * Return the index into tab at which {a,b} match elements {[0],[1]} of tab.
116  * If there is no such matching pair then size is returned.
117  */
118 int ff_match_2uint16(const uint16_t (*tab)[2], int size, int a, int b);
119 
120 unsigned int avpriv_toupper4(unsigned int x);
121 
122 /**
123  * does needed setup of pkt_pts/pos and such for (re)get_buffer();
124  */
126 
127 /**
128  * Remove and free all side data from packet.
129  */
131 
132 extern volatile int ff_avcodec_locked;
133 int ff_lock_avcodec(AVCodecContext *log_ctx);
134 int ff_unlock_avcodec(void);
135 
136 int avpriv_lock_avformat(void);
137 int avpriv_unlock_avformat(void);
138 
139 /**
140  * Maximum size in bytes of extradata.
141  * This value was chosen such that every bit of the buffer is
142  * addressable by a 32-bit signed integer as used by get_bits.
143  */
144 #define FF_MAX_EXTRADATA_SIZE ((1 << 28) - FF_INPUT_BUFFER_PADDING_SIZE)
145 
146 /**
147  * Check AVPacket size and/or allocate data.
148  *
149  * Encoders supporting AVCodec.encode2() can use this as a convenience to
150  * ensure the output packet data is large enough, whether provided by the user
151  * or allocated in this function.
152  *
153  * @param avctx the AVCodecContext of the encoder
154  * @param avpkt the AVPacket
155  * If avpkt->data is already set, avpkt->size is checked
156  * to ensure it is large enough.
157  * If avpkt->data is NULL, a new buffer is allocated.
158  * avpkt->size is set to the specified size.
159  * All other AVPacket fields will be reset with av_init_packet().
160  * @param size the minimum required packet size
161  * @return 0 on success, negative error code on failure
162  */
163 int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int size);
164 
165 int ff_alloc_packet(AVPacket *avpkt, int size);
166 
167 /**
168  * Rescale from sample rate to AVCodecContext.time_base.
169  */
171  int64_t samples)
172 {
173  if(samples == AV_NOPTS_VALUE)
174  return AV_NOPTS_VALUE;
175  return av_rescale_q(samples, (AVRational){ 1, avctx->sample_rate },
176  avctx->time_base);
177 }
178 
179 /**
180  * Get a buffer for a frame. This is a wrapper around
181  * AVCodecContext.get_buffer() and should be used instead calling get_buffer()
182  * directly.
183  */
185 
187 
189 
191 
192 /**
193  * Call avcodec_open2 recursively by decrementing counter, unlocking mutex,
194  * calling the function and then restoring again. Assumes the mutex is
195  * already locked
196  */
198 
199 /**
200  * Call avcodec_close recursively, counterpart to avcodec_open2_recursive.
201  */
203 
204 /**
205  * Finalize buf into extradata and set its size appropriately.
206  */
207 int avpriv_bprint_to_extradata(AVCodecContext *avctx, struct AVBPrint *buf);
208 
209 #endif /* AVCODEC_INTERNAL_H */