FFmpeg
ljpegenc.c
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1 /*
2  * lossless JPEG encoder
3  * Copyright (c) 2000, 2001 Fabrice Bellard
4  * Copyright (c) 2003 Alex Beregszaszi
5  * Copyright (c) 2003-2004 Michael Niedermayer
6  *
7  * Support for external huffman table, various fixes (AVID workaround),
8  * aspecting, new decode_frame mechanism and apple mjpeg-b support
9  * by Alex Beregszaszi
10  *
11  * This file is part of FFmpeg.
12  *
13  * FFmpeg is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU Lesser General Public
15  * License as published by the Free Software Foundation; either
16  * version 2.1 of the License, or (at your option) any later version.
17  *
18  * FFmpeg is distributed in the hope that it will be useful,
19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21  * Lesser General Public License for more details.
22  *
23  * You should have received a copy of the GNU Lesser General Public
24  * License along with FFmpeg; if not, write to the Free Software
25  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26  */
27 
28 /**
29  * @file
30  * lossless JPEG encoder.
31  */
32 
33 #include "libavutil/frame.h"
34 #include "libavutil/mem.h"
35 #include "libavutil/opt.h"
36 #include "libavutil/pixdesc.h"
37 
38 #include "avcodec.h"
39 #include "idctdsp.h"
40 #include "internal.h"
41 #include "jpegtables.h"
42 #include "mathops.h"
43 #include "mjpegenc_common.h"
44 #include "mjpeg.h"
45 
46 typedef struct LJpegEncContext {
47  AVClass *class;
50  uint16_t matrix[64];
51 
52  int vsample[4];
53  int hsample[4];
54 
55  uint16_t huff_code_dc_luminance[12];
59 
60  uint16_t (*scratch)[4];
61  int pred;
63 
65  const AVFrame *frame)
66 {
67  LJpegEncContext *s = avctx->priv_data;
68  const int width = frame->width;
69  const int height = frame->height;
70  const int linesize = frame->linesize[0];
71  uint16_t (*buffer)[4] = s->scratch;
72  int left[4], top[4], topleft[4];
73  int x, y, i;
74 
75 #if FF_API_PRIVATE_OPT
77  if (avctx->prediction_method)
78  s->pred = avctx->prediction_method + 1;
80 #endif
81 
82  for (i = 0; i < 4; i++)
83  buffer[0][i] = 1 << (9 - 1);
84 
85  for (y = 0; y < height; y++) {
86  const int modified_predictor = y ? s->pred : 1;
87  uint8_t *ptr = frame->data[0] + (linesize * y);
88 
89  if (pb->buf_end - pb->buf - (put_bits_count(pb) >> 3) < width * 4 * 4) {
90  av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");
91  return -1;
92  }
93 
94  for (i = 0; i < 4; i++)
95  top[i]= left[i]= topleft[i]= buffer[0][i];
96 
97  for (x = 0; x < width; x++) {
98  if(avctx->pix_fmt == AV_PIX_FMT_BGR24){
99  buffer[x][1] = ptr[3 * x + 0] - ptr[3 * x + 1] + 0x100;
100  buffer[x][2] = ptr[3 * x + 2] - ptr[3 * x + 1] + 0x100;
101  buffer[x][0] = (ptr[3 * x + 0] + 2 * ptr[3 * x + 1] + ptr[3 * x + 2]) >> 2;
102  }else{
103  buffer[x][1] = ptr[4 * x + 0] - ptr[4 * x + 1] + 0x100;
104  buffer[x][2] = ptr[4 * x + 2] - ptr[4 * x + 1] + 0x100;
105  buffer[x][0] = (ptr[4 * x + 0] + 2 * ptr[4 * x + 1] + ptr[4 * x + 2]) >> 2;
106  if (avctx->pix_fmt == AV_PIX_FMT_BGRA)
107  buffer[x][3] = ptr[4 * x + 3];
108  }
109 
110  for (i = 0; i < 3 + (avctx->pix_fmt == AV_PIX_FMT_BGRA); i++) {
111  int pred, diff;
112 
113  PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
114 
115  topleft[i] = top[i];
116  top[i] = buffer[x+1][i];
117 
118  left[i] = buffer[x][i];
119 
120  diff = ((left[i] - pred + 0x100) & 0x1FF) - 0x100;
121 
122  if (i == 0 || i == 3)
124  else
126  }
127  }
128  }
129 
130  return 0;
131 }
132 
134  const AVFrame *frame, int predictor,
135  int mb_x, int mb_y)
136 {
137  int i;
138 
139  if (mb_x == 0 || mb_y == 0) {
140  for (i = 0; i < 3; i++) {
141  uint8_t *ptr;
142  int x, y, h, v, linesize;
143  h = s->hsample[i];
144  v = s->vsample[i];
145  linesize = frame->linesize[i];
146 
147  for (y = 0; y < v; y++) {
148  for (x = 0; x < h; x++) {
149  int pred;
150 
151  ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
152  if (y == 0 && mb_y == 0) {
153  if (x == 0 && mb_x == 0)
154  pred = 128;
155  else
156  pred = ptr[-1];
157  } else {
158  if (x == 0 && mb_x == 0) {
159  pred = ptr[-linesize];
160  } else {
161  PREDICT(pred, ptr[-linesize - 1], ptr[-linesize],
162  ptr[-1], predictor);
163  }
164  }
165 
166  if (i == 0)
167  ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly
168  else
170  }
171  }
172  }
173  } else {
174  for (i = 0; i < 3; i++) {
175  uint8_t *ptr;
176  int x, y, h, v, linesize;
177  h = s->hsample[i];
178  v = s->vsample[i];
179  linesize = frame->linesize[i];
180 
181  for (y = 0; y < v; y++) {
182  for (x = 0; x < h; x++) {
183  int pred;
184 
185  ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
186  PREDICT(pred, ptr[-linesize - 1], ptr[-linesize], ptr[-1], predictor);
187 
188  if (i == 0)
189  ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly
190  else
192  }
193  }
194  }
195  }
196 }
197 
199  const AVFrame *frame)
200 {
201  LJpegEncContext *s = avctx->priv_data;
202  const int mb_width = (avctx->width + s->hsample[0] - 1) / s->hsample[0];
203  const int mb_height = (avctx->height + s->vsample[0] - 1) / s->vsample[0];
204  int mb_x, mb_y;
205 
206 #if FF_API_PRIVATE_OPT
208  if (avctx->prediction_method)
209  s->pred = avctx->prediction_method + 1;
211 #endif
212 
213  for (mb_y = 0; mb_y < mb_height; mb_y++) {
214  if (pb->buf_end - pb->buf - (put_bits_count(pb) >> 3) <
215  mb_width * 4 * 3 * s->hsample[0] * s->vsample[0]) {
216  av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");
217  return -1;
218  }
219 
220  for (mb_x = 0; mb_x < mb_width; mb_x++)
221  ljpeg_encode_yuv_mb(s, pb, frame, s->pred, mb_x, mb_y);
222  }
223 
224  return 0;
225 }
226 
228  const AVFrame *pict, int *got_packet)
229 {
230  LJpegEncContext *s = avctx->priv_data;
231  PutBitContext pb;
232  const int width = avctx->width;
233  const int height = avctx->height;
234  const int mb_width = (width + s->hsample[0] - 1) / s->hsample[0];
235  const int mb_height = (height + s->vsample[0] - 1) / s->vsample[0];
236  int max_pkt_size = AV_INPUT_BUFFER_MIN_SIZE;
237  int ret, header_bits;
238 
239  if( avctx->pix_fmt == AV_PIX_FMT_BGR0
240  || avctx->pix_fmt == AV_PIX_FMT_BGR24)
241  max_pkt_size += width * height * 3 * 4;
242  else if(avctx->pix_fmt == AV_PIX_FMT_BGRA)
243  max_pkt_size += width * height * 4 * 4;
244  else {
245  max_pkt_size += mb_width * mb_height * 3 * 4
246  * s->hsample[0] * s->vsample[0];
247  }
248 
249  if ((ret = ff_alloc_packet2(avctx, pkt, max_pkt_size, 0)) < 0)
250  return ret;
251 
252  init_put_bits(&pb, pkt->data, pkt->size);
253 
255  s->pred, s->matrix, s->matrix);
256 
257  header_bits = put_bits_count(&pb);
258 
259  if( avctx->pix_fmt == AV_PIX_FMT_BGR0
260  || avctx->pix_fmt == AV_PIX_FMT_BGRA
261  || avctx->pix_fmt == AV_PIX_FMT_BGR24)
262  ret = ljpeg_encode_bgr(avctx, &pb, pict);
263  else
264  ret = ljpeg_encode_yuv(avctx, &pb, pict);
265  if (ret < 0)
266  return ret;
267 
268  emms_c();
269 
270  ff_mjpeg_escape_FF(&pb, header_bits >> 3);
271  ff_mjpeg_encode_picture_trailer(&pb, header_bits);
272 
273  flush_put_bits(&pb);
274  pkt->size = put_bits_ptr(&pb) - pb.buf;
275  pkt->flags |= AV_PKT_FLAG_KEY;
276  *got_packet = 1;
277 
278  return 0;
279 }
280 
282 {
283  LJpegEncContext *s = avctx->priv_data;
284 
285  av_freep(&s->scratch);
286 
287  return 0;
288 }
289 
291 {
292  LJpegEncContext *s = avctx->priv_data;
293 
294  if ((avctx->pix_fmt == AV_PIX_FMT_YUV420P ||
295  avctx->pix_fmt == AV_PIX_FMT_YUV422P ||
296  avctx->pix_fmt == AV_PIX_FMT_YUV444P ||
297  avctx->color_range == AVCOL_RANGE_MPEG) &&
299  av_log(avctx, AV_LOG_ERROR,
300  "Limited range YUV is non-standard, set strict_std_compliance to "
301  "at least unofficial to use it.\n");
302  return AVERROR(EINVAL);
303  }
304 
305 #if FF_API_CODED_FRAME
308  avctx->coded_frame->key_frame = 1;
310 #endif
311 
312  s->scratch = av_malloc_array(avctx->width + 1, sizeof(*s->scratch));
313  if (!s->scratch)
314  return AVERROR(ENOMEM);
315 
316  ff_idctdsp_init(&s->idsp, avctx);
319 
320  ff_mjpeg_init_hvsample(avctx, s->hsample, s->vsample);
321 
330 
331  return 0;
332 }
333 
334 #define OFFSET(x) offsetof(LJpegEncContext, x)
335 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
336 static const AVOption options[] = {
337 { "pred", "Prediction method", OFFSET(pred), AV_OPT_TYPE_INT, { .i64 = 1 }, 1, 3, VE, "pred" },
338  { "left", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, "pred" },
339  { "plane", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, "pred" },
340  { "median", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 3 }, INT_MIN, INT_MAX, VE, "pred" },
341 
342  { NULL},
343 };
344 
345 static const AVClass ljpeg_class = {
346  .class_name = "ljpeg",
347  .item_name = av_default_item_name,
348  .option = options,
349  .version = LIBAVUTIL_VERSION_INT,
350 };
351 
353  .name = "ljpeg",
354  .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),
355  .type = AVMEDIA_TYPE_VIDEO,
356  .id = AV_CODEC_ID_LJPEG,
357  .priv_data_size = sizeof(LJpegEncContext),
358  .priv_class = &ljpeg_class,
360  .encode2 = ljpeg_encode_frame,
361  .close = ljpeg_encode_close,
362  .capabilities = AV_CODEC_CAP_FRAME_THREADS,
363  .pix_fmts = (const enum AVPixelFormat[]){
368 };
AVCodec ff_ljpeg_encoder
Definition: ljpegenc.c:352
#define NULL
Definition: coverity.c:32
IDCTDSPContext idsp
Definition: ljpegenc.c:48
This structure describes decoded (raw) audio or video data.
Definition: frame.h:314
AVOption.
Definition: opt.h:248
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:71
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
Memory handling functions.
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
enum AVColorRange color_range
MPEG vs JPEG YUV range.
Definition: avcodec.h:1166
Scantable.
Definition: idctdsp.h:31
int hsample[4]
Definition: ljpegenc.c:53
int size
Definition: packet.h:364
void ff_mjpeg_init_hvsample(AVCodecContext *avctx, int hsample[4], int vsample[4])
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
static const AVClass ljpeg_class
Definition: ljpegenc.c:345
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:741
static AVPacket pkt
AVCodec.
Definition: codec.h:190
MJPEG encoder and decoder.
uint16_t(* scratch)[4]
Definition: ljpegenc.c:60
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
uint8_t huff_size_dc_chrominance[12]
Definition: ljpegenc.c:58
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:33
uint8_t
#define av_cold
Definition: attributes.h:88
AVOptions.
const uint8_t avpriv_mjpeg_bits_dc_luminance[17]
Definition: jpegtables.c:65
void ff_mjpeg_build_huffman_codes(uint8_t *huff_size, uint16_t *huff_code, const uint8_t *bits_table, const uint8_t *val_table)
#define height
uint8_t * data
Definition: packet.h:363
planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting col...
Definition: pixfmt.h:79
#define AV_INPUT_BUFFER_MIN_SIZE
minimum encoding buffer size Used to avoid some checks during header writing.
Definition: avcodec.h:222
#define av_log(a,...)
#define FF_COMPLIANCE_UNOFFICIAL
Allow unofficial extensions.
Definition: avcodec.h:1600
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: packet.h:401
#define PREDICT(ret, topleft, top, left, predictor)
Definition: mjpeg.h:118
int width
Definition: frame.h:372
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:194
static uint8_t * put_bits_ptr(PutBitContext *s)
Return the pointer to the byte where the bitstream writer will put the next bit.
Definition: put_bits.h:349
const uint8_t avpriv_mjpeg_bits_dc_chrominance[17]
Definition: jpegtables.c:70
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:115
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:95
uint8_t * buf
Definition: put_bits.h:54
const char * name
Name of the codec implementation.
Definition: codec.h:197
void ff_mjpeg_encode_picture_trailer(PutBitContext *pb, int header_bits)
uint16_t matrix[64]
Definition: ljpegenc.c:50
ScanTable scantable
Definition: ljpegenc.c:49
#define AV_CODEC_CAP_FRAME_THREADS
Codec supports frame-level multithreading.
Definition: codec.h:106
int flags
A combination of AV_PKT_FLAG values.
Definition: packet.h:369
reference-counted frame API
static int put_bits_count(PutBitContext *s)
Definition: put_bits.h:83
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:70
static int ljpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet)
Definition: ljpegenc.c:227
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:397
static av_cold int ljpeg_encode_init(AVCodecContext *avctx)
Definition: ljpegenc.c:290
static void predictor(uint8_t *src, ptrdiff_t size)
Definition: exrenc.c:156
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:78
#define width
int width
picture width / height.
Definition: avcodec.h:704
static av_cold int ljpeg_encode_close(AVCodecContext *avctx)
Definition: ljpegenc.c:281
uint16_t huff_code_dc_chrominance[12]
Definition: ljpegenc.c:56
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
void ff_mjpeg_escape_FF(PutBitContext *pb, int start)
uint8_t idct_permutation[64]
IDCT input permutation.
Definition: idctdsp.h:96
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
#define OFFSET(x)
Definition: ljpegenc.c:334
void ff_mjpeg_encode_dc(PutBitContext *pb, int val, uint8_t *huff_size, uint16_t *huff_code)
Libavcodec external API header.
attribute_deprecated int prediction_method
Definition: avcodec.h:890
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:345
main external API structure.
Definition: avcodec.h:531
Tag MUST be and< 10hcoeff half pel interpolation filter coefficients, hcoeff[0] are the 2 middle coefficients[1] are the next outer ones and so on, resulting in a filter like:...eff[2], hcoeff[1], hcoeff[0], hcoeff[0], hcoeff[1], hcoeff[2]...the sign of the coefficients is not explicitly stored but alternates after each coeff and coeff[0] is positive, so...,+,-,+,-,+,+,-,+,-,+,...hcoeff[0] is not explicitly stored but found by subtracting the sum of all stored coefficients with signs from 32 hcoeff[0]=32-hcoeff[1]-hcoeff[2]-...a good choice for hcoeff and htaps is htaps=6 hcoeff={40,-10, 2}an alternative which requires more computations at both encoder and decoder side and may or may not be better is htaps=8 hcoeff={42,-14, 6,-2}ref_frames minimum of the number of available reference frames and max_ref_frames for example the first frame after a key frame always has ref_frames=1spatial_decomposition_type wavelet type 0 is a 9/7 symmetric compact integer wavelet 1 is a 5/3 symmetric compact integer wavelet others are reserved stored as delta from last, last is reset to 0 if always_reset||keyframeqlog quality(logarithmic quantizer scale) stored as delta from last, last is reset to 0 if always_reset||keyframemv_scale stored as delta from last, last is reset to 0 if always_reset||keyframe FIXME check that everything works fine if this changes between framesqbias dequantization bias stored as delta from last, last is reset to 0 if always_reset||keyframeblock_max_depth maximum depth of the block tree stored as delta from last, last is reset to 0 if always_reset||keyframequant_table quantization tableHighlevel bitstream structure:==============================--------------------------------------------|Header|--------------------------------------------|------------------------------------|||Block0||||split?||||yes no||||.........intra?||||:Block01:yes no||||:Block02:.................||||:Block03::y DC::ref index:||||:Block04::cb DC::motion x:||||.........:cr DC::motion y:||||.................|||------------------------------------||------------------------------------|||Block1|||...|--------------------------------------------|------------------------------------|||Y subbands||Cb subbands||Cr subbands||||------||------||------|||||LL0||HL0||||LL0||HL0||||LL0||HL0|||||------||------||------||||------||------||------|||||LH0||HH0||||LH0||HH0||||LH0||HH0|||||------||------||------||||------||------||------|||||HL1||LH1||||HL1||LH1||||HL1||LH1|||||------||------||------||||------||------||------|||||HH1||HL2||||HH1||HL2||||HH1||HL2|||||...||...||...|||------------------------------------|--------------------------------------------Decoding process:=================------------|||Subbands|------------||||------------|Intra DC||||LL0 subband prediction------------|\Dequantization-------------------\||Reference frames|\IDWT|--------------|Motion\|||Frame 0||Frame 1||Compensation.OBMC v-------|--------------|--------------.\------> Frame n output Frame Frame<----------------------------------/|...|-------------------Range Coder:============Binary Range Coder:-------------------The implemented range coder is an adapted version based upon"Range encoding: an algorithm for removing redundancy from a digitised message."by G.N.N.Martin.The symbols encoded by the Snow range coder are bits(0|1).The associated probabilities are not fix but change depending on the symbol mix seen so far.bit seen|new state---------+-----------------------------------------------0|256-state_transition_table[256-old_state];1|state_transition_table[old_state];state_transition_table={0, 0, 0, 0, 0, 0, 0, 0, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 171, 172, 173, 174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 190, 191, 192, 194, 194, 195, 196, 197, 198, 199, 200, 201, 202, 202, 204, 205, 206, 207, 208, 209, 209, 210, 211, 212, 213, 215, 215, 216, 217, 218, 219, 220, 220, 222, 223, 224, 225, 226, 227, 227, 229, 229, 230, 231, 232, 234, 234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248, 248, 0, 0, 0, 0, 0, 0, 0};FIXME Range Coding of integers:-------------------------FIXME Neighboring Blocks:===================left and top are set to the respective blocks unless they are outside of the image in which case they are set to the Null block top-left is set to the top left block unless it is outside of the image in which case it is set to the left block if this block has no larger parent block or it is at the left side of its parent block and the top right block is not outside of the image then the top right block is used for top-right else the top-left block is used Null block y, cb, cr are 128 level, ref, mx and my are 0 Motion Vector Prediction:=========================1.the motion vectors of all the neighboring blocks are scaled to compensate for the difference of reference frames scaled_mv=(mv *(256 *(current_reference+1)/(mv.reference+1))+128)> the median of the scaled left
Definition: snow.txt:206
uint8_t * buf_end
Definition: put_bits.h:54
const uint8_t avpriv_mjpeg_val_dc[12]
Definition: jpegtables.c:67
#define VE
Definition: ljpegenc.c:335
Describe the class of an AVClass context structure.
Definition: log.h:67
const uint8_t ff_zigzag_direct[64]
Definition: mathtables.c:98
packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
Definition: pixfmt.h:240
void ff_mjpeg_encode_picture_header(AVCodecContext *avctx, PutBitContext *pb, ScanTable *intra_scantable, int pred, uint16_t luma_intra_matrix[64], uint16_t chroma_intra_matrix[64])
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:303
static int ljpeg_encode_yuv(AVCodecContext *avctx, PutBitContext *pb, const AVFrame *frame)
Definition: ljpegenc.c:198
static int ljpeg_encode_bgr(AVCodecContext *avctx, PutBitContext *pb, const AVFrame *frame)
Definition: ljpegenc.c:64
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:328
Narrow or limited range content.
Definition: pixfmt.h:569
uint16_t huff_code_dc_luminance[12]
Definition: ljpegenc.c:55
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
#define FF_DISABLE_DEPRECATION_WARNINGS
Definition: internal.h:83
common internal api header.
static void flush_put_bits(PutBitContext *s)
Pad the end of the output stream with zeros.
Definition: put_bits.h:117
uint8_t huff_size_dc_luminance[12]
Definition: ljpegenc.c:57
planar YUV 4:4:4, 24bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV444P and setting col...
Definition: pixfmt.h:80
attribute_deprecated AVFrame * coded_frame
the picture in the bitstream
Definition: avcodec.h:1759
static void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size)
Initialize the PutBitContext s.
Definition: put_bits.h:64
void * priv_data
Definition: avcodec.h:558
static av_always_inline int diff(const uint32_t a, const uint32_t b)
av_cold void ff_init_scantable(uint8_t *permutation, ScanTable *st, const uint8_t *src_scantable)
Definition: idctdsp.c:29
static void ljpeg_encode_yuv_mb(LJpegEncContext *s, PutBitContext *pb, const AVFrame *frame, int predictor, int mb_x, int mb_y)
Definition: ljpegenc.c:133
av_cold void ff_idctdsp_init(IDCTDSPContext *c, AVCodecContext *avctx)
Definition: idctdsp.c:238
#define FF_ENABLE_DEPRECATION_WARNINGS
Definition: internal.h:84
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:392
int height
Definition: frame.h:372
#define av_freep(p)
#define av_malloc_array(a, b)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: packet.h:340
int strict_std_compliance
strictly follow the standard (MPEG-4, ...).
Definition: avcodec.h:1596
static const AVOption options[]
Definition: ljpegenc.c:336
int i
Definition: input.c:407
GLuint buffer
Definition: opengl_enc.c:101
int vsample[4]
Definition: ljpegenc.c:52