lavc: Rename avpriv_mpv_find_start_code after moving out from mpegvideo
[libav.git] / libavcodec / internal.h
1 /*
2 * This file is part of Libav.
3 *
4 * Libav 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 * Libav 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 Libav; 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"
30 #include "libavutil/mathematics.h"
31 #include "libavutil/pixfmt.h"
32 #include "avcodec.h"
33 #include "config.h"
34
35 #define FF_SANE_NB_CHANNELS 63U
36
37 typedef struct FramePool {
38 /**
39 * Pools for each data plane. For audio all the planes have the same size,
40 * so only pools[0] is used.
41 */
42 AVBufferPool *pools[4];
43
44 /*
45 * Pool parameters
46 */
47 int format;
48 int width, height;
49 int stride_align[AV_NUM_DATA_POINTERS];
50 int linesize[4];
51 int planes;
52 int channels;
53 int samples;
54 } FramePool;
55
56 typedef struct AVCodecInternal {
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 /**
66 * Whether to allocate progress for frame threading.
67 *
68 * The codec must set it to 1 if it uses ff_thread_await/report_progress(),
69 * then progress will be allocated in ff_thread_get_buffer(). The frames
70 * then MUST be freed with ff_thread_release_buffer().
71 *
72 * If the codec does not need to call the progress functions (there are no
73 * dependencies between the frames), it should leave this at 0. Then it can
74 * decode straight to the user-provided frames (which the user will then
75 * free with av_frame_unref()), there is no need to call
76 * ff_thread_release_buffer().
77 */
78 int allocate_progress;
79
80 /**
81 * An audio frame with less than required samples has been submitted and
82 * padded with silence. Reject all subsequent frames.
83 */
84 int last_audio_frame;
85
86 AVFrame to_free;
87
88 FramePool *pool;
89 } AVCodecInternal;
90
91 struct AVCodecDefault {
92 const uint8_t *key;
93 const uint8_t *value;
94 };
95
96 /**
97 * Return the hardware accelerated codec for codec codec_id and
98 * pixel format pix_fmt.
99 *
100 * @param codec_id the codec to match
101 * @param pix_fmt the pixel format to match
102 * @return the hardware accelerated codec, or NULL if none was found.
103 */
104 AVHWAccel *ff_find_hwaccel(enum AVCodecID codec_id, enum AVPixelFormat pix_fmt);
105
106 /**
107 * Return the index into tab at which {a,b} match elements {[0],[1]} of tab.
108 * If there is no such matching pair then size is returned.
109 */
110 int ff_match_2uint16(const uint16_t (*tab)[2], int size, int a, int b);
111
112 unsigned int avpriv_toupper4(unsigned int x);
113
114 int avpriv_lock_avformat(void);
115 int avpriv_unlock_avformat(void);
116
117 /**
118 * Maximum size in bytes of extradata.
119 * This value was chosen such that every bit of the buffer is
120 * addressable by a 32-bit signed integer as used by get_bits.
121 */
122 #define FF_MAX_EXTRADATA_SIZE ((1 << 28) - FF_INPUT_BUFFER_PADDING_SIZE)
123
124 /**
125 * Check AVPacket size and/or allocate data.
126 *
127 * Encoders supporting AVCodec.encode2() can use this as a convenience to
128 * ensure the output packet data is large enough, whether provided by the user
129 * or allocated in this function.
130 *
131 * @param avpkt the AVPacket
132 * If avpkt->data is already set, avpkt->size is checked
133 * to ensure it is large enough.
134 * If avpkt->data is NULL, a new buffer is allocated.
135 * avpkt->size is set to the specified size.
136 * All other AVPacket fields will be reset with av_init_packet().
137 * @param size the minimum required packet size
138 * @return 0 on success, negative error code on failure
139 */
140 int ff_alloc_packet(AVPacket *avpkt, int size);
141
142 /**
143 * Rescale from sample rate to AVCodecContext.time_base.
144 */
145 static av_always_inline int64_t ff_samples_to_time_base(AVCodecContext *avctx,
146 int64_t samples)
147 {
148 return av_rescale_q(samples, (AVRational){ 1, avctx->sample_rate },
149 avctx->time_base);
150 }
151
152 /**
153 * Get a buffer for a frame. This is a wrapper around
154 * AVCodecContext.get_buffer() and should be used instead calling get_buffer()
155 * directly.
156 */
157 int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags);
158
159 /**
160 * Identical in function to av_frame_make_writable(), except it uses
161 * ff_get_buffer() to allocate the buffer when needed.
162 */
163 int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame);
164
165 const uint8_t *avpriv_find_start_code(const uint8_t *restrict p,
166 const uint8_t *end,
167 uint32_t *restrict state);
168
169 #endif /* AVCODEC_INTERNAL_H */