FFmpeg
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 /**
37  * The codec does not modify any global variables in the init function,
38  * allowing to call the init function without locking any global mutexes.
39  */
40 #define FF_CODEC_CAP_INIT_THREADSAFE (1 << 0)
41 /**
42  * The codec allows calling the close function for deallocation even if
43  * the init function returned a failure. Without this capability flag, a
44  * codec does such cleanup internally when returning failures from the
45  * init function and does not expect the close function to be called at
46  * all.
47  */
48 #define FF_CODEC_CAP_INIT_CLEANUP (1 << 1)
49 /**
50  * Decoders marked with FF_CODEC_CAP_SETS_PKT_DTS want to set
51  * AVFrame.pkt_dts manually. If the flag is set, decode.c won't overwrite
52  * this field. If it's unset, decode.c tries to guess the pkt_dts field
53  * from the input AVPacket.
54  */
55 #define FF_CODEC_CAP_SETS_PKT_DTS (1 << 2)
56 /**
57  * The decoder extracts and fills its parameters even if the frame is
58  * skipped due to the skip_frame setting.
59  */
60 #define FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM (1 << 3)
61 /**
62  * The decoder sets the cropping fields in the output frames manually.
63  * If this cap is set, the generic code will initialize output frame
64  * dimensions to coded rather than display values.
65  */
66 #define FF_CODEC_CAP_EXPORTS_CROPPING (1 << 4)
67 /**
68  * Codec initializes slice-based threading with a main function
69  */
70 #define FF_CODEC_CAP_SLICE_THREAD_HAS_MF (1 << 5)
71 /*
72  * The codec supports frame threading and has inter-frame dependencies, so it
73  * uses ff_thread_report/await_progress().
74  */
75 #define FF_CODEC_CAP_ALLOCATE_PROGRESS (1 << 6)
76 
77 /**
78  * AVCodec.codec_tags termination value
79  */
80 #define FF_CODEC_TAGS_END -1
81 
82 
83 #ifdef TRACE
84 # define ff_tlog(ctx, ...) av_log(ctx, AV_LOG_TRACE, __VA_ARGS__)
85 #else
86 # define ff_tlog(ctx, ...) do { } while(0)
87 #endif
88 
89 
90 #define FF_DEFAULT_QUANT_BIAS 999999
91 
92 #define FF_QSCALE_TYPE_MPEG1 0
93 #define FF_QSCALE_TYPE_MPEG2 1
94 #define FF_QSCALE_TYPE_H264 2
95 #define FF_QSCALE_TYPE_VP56 3
96 
97 #define FF_SANE_NB_CHANNELS 512U
98 
99 #define FF_SIGNBIT(x) ((x) >> CHAR_BIT * sizeof(x) - 1)
100 
101 #if HAVE_SIMD_ALIGN_64
102 # define STRIDE_ALIGN 64 /* AVX-512 */
103 #elif HAVE_SIMD_ALIGN_32
104 # define STRIDE_ALIGN 32
105 #elif HAVE_SIMD_ALIGN_16
106 # define STRIDE_ALIGN 16
107 #else
108 # define STRIDE_ALIGN 8
109 #endif
110 
111 typedef struct DecodeSimpleContext {
115 
116 typedef struct AVCodecInternal {
117  /**
118  * Whether the parent AVCodecContext is a copy of the context which had
119  * init() called on it.
120  * This is used by multithreading - shared tables and picture pointers
121  * should be freed from the original context only.
122  */
123  int is_copy;
124 
125  /**
126  * An audio frame with less than required samples has been submitted and
127  * padded with silence. Reject all subsequent frames.
128  */
130 
132 
134 
135  void *thread_ctx;
136 
139 
140  /**
141  * Properties (timestamps+side data) extracted from the last packet passed
142  * for decoding.
143  */
145 
146  /**
147  * temporary buffer used for encoders to store their bitstream
148  */
150  unsigned int byte_buffer_size;
151 
153 
154  /**
155  * Number of audio samples to skip at the start of the next decoded frame
156  */
158 
159  /**
160  * hwaccel-specific private data
161  */
163 
164  /**
165  * checks API usage: after codec draining, flush is required to resume operation
166  */
167  int draining;
168 
169  /**
170  * buffers for using new encode/decode API through legacy API
171  */
173  int buffer_pkt_valid; // encoding: packet without data can be valid
177  /* this variable is set by the decoder internals to signal to the old
178  * API compat wrappers the amount of data consumed from the last packet */
180  /* when a partial packet has been consumed, this stores the remaining size
181  * of the packet (that should be submitted in the next decode call */
184 
186 
188 
189  /* to prevent infinite loop on errors when draining */
191 
192  /* used when avctx flag AV_CODEC_FLAG_DROPCHANGED is set */
195  int initial_width, initial_height;
200 
202  const uint8_t *key;
203  const uint8_t *value;
204 };
205 
206 extern const uint8_t ff_log2_run[41];
207 
208 /**
209  * Return the index into tab at which {a,b} match elements {[0],[1]} of tab.
210  * If there is no such matching pair then size is returned.
211  */
212 int ff_match_2uint16(const uint16_t (*tab)[2], int size, int a, int b);
213 
214 unsigned int avpriv_toupper4(unsigned int x);
215 
216 void ff_color_frame(AVFrame *frame, const int color[4]);
217 
218 /**
219  * Maximum size in bytes of extradata.
220  * This value was chosen such that every bit of the buffer is
221  * addressable by a 32-bit signed integer as used by get_bits.
222  */
223 #define FF_MAX_EXTRADATA_SIZE ((1 << 28) - AV_INPUT_BUFFER_PADDING_SIZE)
224 
225 /**
226  * Check AVPacket size and/or allocate data.
227  *
228  * Encoders supporting AVCodec.encode2() can use this as a convenience to
229  * ensure the output packet data is large enough, whether provided by the user
230  * or allocated in this function.
231  *
232  * @param avctx the AVCodecContext of the encoder
233  * @param avpkt the AVPacket
234  * If avpkt->data is already set, avpkt->size is checked
235  * to ensure it is large enough.
236  * If avpkt->data is NULL, a new buffer is allocated.
237  * avpkt->size is set to the specified size.
238  * All other AVPacket fields will be reset with av_init_packet().
239  * @param size the minimum required packet size
240  * @param min_size This is a hint to the allocation algorithm, which indicates
241  * to what minimal size the caller might later shrink the packet
242  * to. Encoders often allocate packets which are larger than the
243  * amount of data that is written into them as the exact amount is
244  * not known at the time of allocation. min_size represents the
245  * size a packet might be shrunk to by the caller. Can be set to
246  * 0. setting this roughly correctly allows the allocation code
247  * to choose between several allocation strategies to improve
248  * speed slightly.
249  * @return non negative on success, negative error code on failure
250  */
251 int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size);
252 
254 
255 /**
256  * Rescale from sample rate to AVCodecContext.time_base.
257  */
259  int64_t samples)
260 {
261  if(samples == AV_NOPTS_VALUE)
262  return AV_NOPTS_VALUE;
263  return av_rescale_q(samples, (AVRational){ 1, avctx->sample_rate },
264  avctx->time_base);
265 }
266 
267 /**
268  * 2^(x) for integer x
269  * @return correctly rounded float
270  */
271 static av_always_inline float ff_exp2fi(int x) {
272  /* Normal range */
273  if (-126 <= x && x <= 128)
274  return av_int2float((x+127) << 23);
275  /* Too large */
276  else if (x > 128)
277  return INFINITY;
278  /* Subnormal numbers */
279  else if (x > -150)
280  return av_int2float(1 << (x+149));
281  /* Negligibly small */
282  else
283  return 0;
284 }
285 
286 /**
287  * Get a buffer for a frame. This is a wrapper around
288  * AVCodecContext.get_buffer() and should be used instead calling get_buffer()
289  * directly.
290  */
291 int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags);
292 
293 #define FF_REGET_BUFFER_FLAG_READONLY 1 ///< the returned buffer does not need to be writable
294 /**
295  * Identical in function to ff_get_buffer(), except it reuses the existing buffer
296  * if available.
297  */
298 int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags);
299 
301 
303 
304 /**
305  * Call avcodec_open2 recursively by decrementing counter, unlocking mutex,
306  * calling the function and then restoring again. Assumes the mutex is
307  * already locked
308  */
310 
311 /**
312  * Finalize buf into extradata and set its size appropriately.
313  */
314 int avpriv_bprint_to_extradata(AVCodecContext *avctx, struct AVBPrint *buf);
315 
316 const uint8_t *avpriv_find_start_code(const uint8_t *p,
317  const uint8_t *end,
318  uint32_t *state);
319 
321 
322 /**
323  * Check that the provided frame dimensions are valid and set them on the codec
324  * context.
325  */
327 
328 /**
329  * Check that the provided sample aspect ratio is valid and set it on the codec
330  * context.
331  */
332 int ff_set_sar(AVCodecContext *avctx, AVRational sar);
333 
334 /**
335  * Add or update AV_FRAME_DATA_MATRIXENCODING side data.
336  */
338  enum AVMatrixEncoding matrix_encoding);
339 
340 /**
341  * Select the (possibly hardware accelerated) pixel format.
342  * This is a wrapper around AVCodecContext.get_format() and should be used
343  * instead of calling get_format() directly.
344  *
345  * The list of pixel formats must contain at least one valid entry, and is
346  * terminated with AV_PIX_FMT_NONE. If it is possible to decode to software,
347  * the last entry in the list must be the most accurate software format.
348  * If it is not possible to decode to software, AVCodecContext.sw_pix_fmt
349  * must be set before calling this function.
350  */
351 int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt);
352 
353 /**
354  * Set various frame properties from the codec context / packet data.
355  */
356 int ff_decode_frame_props(AVCodecContext *avctx, AVFrame *frame);
357 
358 /**
359  * Add a CPB properties side data to an encoding context.
360  */
362 
363 int ff_side_data_set_encoder_stats(AVPacket *pkt, int quality, int64_t *error, int error_count, int pict_type);
364 
365 int ff_side_data_set_prft(AVPacket *pkt, int64_t timestamp);
366 
367 /**
368  * Check AVFrame for A53 side data and allocate and fill SEI message with A53 info
369  *
370  * @param frame Raw frame to get A53 side data from
371  * @param prefix_len Number of bytes to allocate before SEI message
372  * @param data Pointer to a variable to store allocated memory
373  * Upon return the variable will hold NULL on error or if frame has no A53 info.
374  * Otherwise it will point to prefix_len uninitialized bytes followed by
375  * *sei_size SEI message
376  * @param sei_size Pointer to a variable to store generated SEI message length
377  * @return Zero on success, negative error code on failure
378  */
379 int ff_alloc_a53_sei(const AVFrame *frame, size_t prefix_len,
380  void **data, size_t *sei_size);
381 
382 /**
383  * Get an estimated video bitrate based on frame size, frame rate and coded
384  * bits per pixel.
385  */
386 int64_t ff_guess_coded_bitrate(AVCodecContext *avctx);
387 
388 /**
389  * Check if a value is in the list. If not, return the default value
390  *
391  * @param ctx Context for the log msg
392  * @param val_name Name of the checked value, for log msg
393  * @param array_valid_values Array of valid int, ended with INT_MAX
394  * @param default_value Value return if checked value is not in the array
395  * @return Value or default_value.
396  */
397 int ff_int_from_list_or_default(void *ctx, const char * val_name, int val,
398  const int * array_valid_values, int default_value);
399 
400 void ff_dvdsub_parse_palette(uint32_t *palette, const char *p);
401 
402 #if defined(_WIN32) && CONFIG_SHARED && !defined(BUILDING_avcodec)
403 # define av_export_avcodec __declspec(dllimport)
404 #else
405 # define av_export_avcodec
406 #endif
407 
408 #endif /* AVCODEC_INTERNAL_H */
int nb_draining_errors
Definition: internal.h:190
int ff_thread_can_start_frame(AVCodecContext *avctx)
int ff_reget_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Identical in function to ff_get_buffer(), except it reuses the existing buffer if available...
Definition: decode.c:1957
static struct @314 state
This structure describes decoded (raw) audio or video data.
Definition: frame.h:300
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
AVPacket * last_pkt_props
Properties (timestamps+side data) extracted from the last packet passed for decoding.
Definition: internal.h:144
int changed_frames_dropped
Definition: internal.h:193
AVFrame * to_free
Definition: internal.h:131
int avpriv_codec_get_cap_skip_frame_fill_param(const AVCodec *codec)
Definition: utils.c:496
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:104
static av_always_inline float av_int2float(uint32_t i)
Reinterpret a 32-bit integer as a float.
Definition: intfloat.h:40
The bitstream filter state.
Definition: bsf.h:49
int initial_channels
Definition: internal.h:197
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:36
static AVPacket pkt
static void error(const char *err)
AVCodec.
Definition: avcodec.h:2600
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:780
void ff_color_frame(AVFrame *frame, const int color[4])
Definition: utils.c:412
uint8_t
void * thread_ctx
Definition: internal.h:135
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int ff_decode_frame_props(AVCodecContext *avctx, AVFrame *frame)
Set various frame properties from the codec context / packet data.
Definition: decode.c:1685
void * frame_thread_encoder
Definition: internal.h:152
#define height
size_t compat_decode_consumed
Definition: internal.h:179
int ff_set_sar(AVCodecContext *avctx, AVRational sar)
Check that the provided sample aspect ratio is valid and set it on the codec context.
Definition: utils.c:119
ptrdiff_t size
Definition: opengl_enc.c:100
int initial_format
Definition: internal.h:194
int avpriv_bprint_to_extradata(AVCodecContext *avctx, struct AVBPrint *buf)
Finalize buf into extradata and set its size appropriately.
Definition: utils.c:1921
const uint8_t * avpriv_find_start_code(const uint8_t *p, const uint8_t *end, uint32_t *state)
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
AVBSFContext * bsf
Definition: internal.h:138
int ff_codec_open2_recursive(AVCodecContext *avctx, const AVCodec *codec, AVDictionary **options)
Call avcodec_open2 recursively by decrementing counter, unlocking mutex, calling the function and the...
Definition: utils.c:536
int is_copy
Whether the parent AVCodecContext is a copy of the context which had init() called on it...
Definition: internal.h:123
AVFrame * buffer_frame
Definition: internal.h:174
static av_always_inline float ff_exp2fi(int x)
2^(x) for integer x
Definition: internal.h:271
int64_t ff_guess_coded_bitrate(AVCodecContext *avctx)
Get an estimated video bitrate based on frame size, frame rate and coded bits per pixel...
Definition: utils.c:2238
#define b
Definition: input.c:41
audio channel layout utility functions
#define width
AVFrame * compat_decode_frame
Definition: internal.h:183
AVPacket * in_pkt
Definition: internal.h:112
AVFormatContext * ctx
Definition: movenc.c:48
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about quality
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
DecodeSimpleContext ds
Definition: internal.h:137
int draining
checks API usage: after codec draining, flush is required to resume operation
Definition: internal.h:167
int ff_side_data_update_matrix_encoding(AVFrame *frame, enum AVMatrixEncoding matrix_encoding)
Add or update AV_FRAME_DATA_MATRIXENCODING side data.
Definition: utils.c:134
int ff_get_format(AVCodecContext *avctx, const enum AVPixelFormat *fmt)
Select the (possibly hardware accelerated) pixel format.
Definition: decode.c:1279
This structure describes the bitrate properties of an encoded bitstream.
Definition: avcodec.h:579
Libavcodec external API header.
int compat_decode_warned
Definition: internal.h:176
int sample_rate
samples per second
Definition: avcodec.h:1317
int initial_sample_rate
Definition: internal.h:196
main external API structure.
Definition: avcodec.h:657
int skip_samples_multiplier
Definition: internal.h:187
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1854
int ff_side_data_set_prft(AVPacket *pkt, int64_t timestamp)
Definition: avpacket.c:752
int showed_multi_packet_warning
Definition: internal.h:185
unsigned int avpriv_toupper4(unsigned int x)
Definition: utils.c:1831
Rational number (pair of numerator and denominator).
Definition: rational.h:58
int buffer_pkt_valid
Definition: internal.h:173
int skip_samples
Number of audio samples to skip at the start of the next decoded frame.
Definition: internal.h:157
refcounted data buffer API
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:32
AVBufferRef * pool
Definition: internal.h:133
#define flags(name, subs,...)
Definition: cbs_av1.c:564
#define attribute_deprecated
Definition: attributes.h:94
const uint8_t * key
Definition: internal.h:202
const uint8_t * value
Definition: internal.h:203
int ff_side_data_set_encoder_stats(AVPacket *pkt, int quality, int64_t *error, int error_count, int pict_type)
Definition: avpacket.c:727
AVPacket * buffer_pkt
buffers for using new encode/decode API through legacy API
Definition: internal.h:172
A reference to a data buffer.
Definition: buffer.h:81
void ff_dvdsub_parse_palette(uint32_t *palette, const char *p)
Definition: dvdsub.c:26
const OptionDef options[]
Definition: ffmpeg_opt.c:3387
int avpriv_h264_has_num_reorder_frames(AVCodecContext *avctx)
Definition: h264dec.c:61
void * hwaccel_priv_data
hwaccel-specific private data
Definition: internal.h:162
uint64_t initial_channel_layout
Definition: internal.h:198
AVCPBProperties * ff_add_cpb_side_data(AVCodecContext *avctx)
Add a CPB properties side data to an encoding context.
Definition: utils.c:1991
pixel format definitions
attribute_deprecated int ff_alloc_packet(AVPacket *avpkt, int size)
Definition: encode.c:73
static const struct twinvq_data tab
unsigned int byte_buffer_size
Definition: internal.h:150
int ff_alloc_a53_sei(const AVFrame *frame, size_t prefix_len, void **data, size_t *sei_size)
Check AVFrame for A53 side data and allocate and fill SEI message with A53 info.
Definition: utils.c:2195
size_t compat_decode_partial_size
Definition: internal.h:182
Filter the word “frame” indicates either a video frame or a group of audio samples
#define av_always_inline
Definition: attributes.h:39
const uint8_t ff_log2_run[41]
Definition: bitstream.c:39
static av_always_inline int64_t ff_samples_to_time_base(AVCodecContext *avctx, int64_t samples)
Rescale from sample rate to AVCodecContext.time_base.
Definition: internal.h:258
int ff_int_from_list_or_default(void *ctx, const char *val_name, int val, const int *array_valid_values, int default_value)
Check if a value is in the list.
Definition: utils.c:2259
AVMatrixEncoding
#define INFINITY
Definition: mathematics.h:67
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
static double val(void *priv, double ch)
Definition: aeval.c:76
This structure stores compressed data.
Definition: packet.h:332
uint8_t * byte_buffer
temporary buffer used for encoders to store their bitstream
Definition: internal.h:149
int ff_match_2uint16(const uint16_t(*tab)[2], int size, int a, int b)
Return the index into tab at which {a,b} match elements {[0],[1]} of tab.
Definition: utils.c:1795
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
AVFrame * out_frame
Definition: internal.h:113
int last_audio_frame
An audio frame with less than required samples has been submitted and padded with silence...
Definition: internal.h:129