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1 /*
2  * MJPEG 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  * MJPEG encoder.
31  */
32 
33 #include "config_components.h"
34 
35 #include "libavutil/pixdesc.h"
36 
37 #include "avcodec.h"
38 #include "codec_internal.h"
39 #include "jpegtables.h"
40 #include "mjpegenc_common.h"
41 #include "mjpegenc_huffman.h"
42 #include "mpegvideo.h"
43 #include "mjpeg.h"
44 #include "mjpegenc.h"
45 #include "mpegvideoenc.h"
46 #include "profiles.h"
47 
48 /* The following is the private context of MJPEG/AMV decoder.
49  * Note that when using slice threading only the main thread's
50  * MpegEncContext is followed by a MjpegContext; the other threads
51  * can access this shared context via MpegEncContext.mjpeg. */
52 typedef struct MJPEGEncContext {
53     MpegEncContext mpeg;
54     MJpegContext   mjpeg;
55 } MJPEGEncContext;
56 
init_uni_ac_vlc(const uint8_t huff_size_ac[256],uint8_t * uni_ac_vlc_len)57 static av_cold void init_uni_ac_vlc(const uint8_t huff_size_ac[256],
58                                     uint8_t *uni_ac_vlc_len)
59 {
60     for (int i = 0; i < 128; i++) {
61         int level = i - 64;
62         if (!level)
63             continue;
64         for (int run = 0; run < 64; run++) {
65             int len, code, nbits;
66             int alevel = FFABS(level);
67 
68             len = (run >> 4) * huff_size_ac[0xf0];
69 
70             nbits= av_log2_16bit(alevel) + 1;
71             code = ((15&run) << 4) | nbits;
72 
73             len += huff_size_ac[code] + nbits;
74 
75             uni_ac_vlc_len[UNI_AC_ENC_INDEX(run, i)] = len;
76             // We ignore EOB as its just a constant which does not change generally
77         }
78     }
79 }
80 
mjpeg_encode_picture_header(MpegEncContext * s)81 static void mjpeg_encode_picture_header(MpegEncContext *s)
82 {
83     ff_mjpeg_encode_picture_header(s->avctx, &s->pb, s->picture->f, s->mjpeg_ctx,
84                                    &s->intra_scantable, 0,
85                                    s->intra_matrix, s->chroma_intra_matrix,
86                                    s->slice_context_count > 1);
87 
88     s->esc_pos = put_bytes_count(&s->pb, 0);
89     for (int i = 1; i < s->slice_context_count; i++)
90         s->thread_context[i]->esc_pos = 0;
91 }
92 
ff_mjpeg_amv_encode_picture_header(MpegEncContext * s)93 void ff_mjpeg_amv_encode_picture_header(MpegEncContext *s)
94 {
95     MJPEGEncContext *const m = (MJPEGEncContext*)s;
96     av_assert2(s->mjpeg_ctx == &m->mjpeg);
97     /* s->huffman == HUFFMAN_TABLE_OPTIMAL can only be true for MJPEG. */
98     if (!CONFIG_MJPEG_ENCODER || m->mjpeg.huffman != HUFFMAN_TABLE_OPTIMAL)
99         mjpeg_encode_picture_header(s);
100 }
101 
102 #if CONFIG_MJPEG_ENCODER
103 /**
104  * Encodes and outputs the entire frame in the JPEG format.
105  *
106  * @param s The MpegEncContext.
107  */
mjpeg_encode_picture_frame(MpegEncContext * s)108 static void mjpeg_encode_picture_frame(MpegEncContext *s)
109 {
110     int nbits, code, table_id;
111     MJpegContext *m = s->mjpeg_ctx;
112     uint8_t  *huff_size[4] = { m->huff_size_dc_luminance,
113                                m->huff_size_dc_chrominance,
114                                m->huff_size_ac_luminance,
115                                m->huff_size_ac_chrominance };
116     uint16_t *huff_code[4] = { m->huff_code_dc_luminance,
117                                m->huff_code_dc_chrominance,
118                                m->huff_code_ac_luminance,
119                                m->huff_code_ac_chrominance };
120     size_t total_bits = 0;
121     size_t bytes_needed;
122 
123     s->header_bits = get_bits_diff(s);
124     // Estimate the total size first
125     for (int i = 0; i < m->huff_ncode; i++) {
126         table_id = m->huff_buffer[i].table_id;
127         code = m->huff_buffer[i].code;
128         nbits = code & 0xf;
129 
130         total_bits += huff_size[table_id][code] + nbits;
131     }
132 
133     bytes_needed = (total_bits + 7) / 8;
134     ff_mpv_reallocate_putbitbuffer(s, bytes_needed, bytes_needed);
135 
136     for (int i = 0; i < m->huff_ncode; i++) {
137         table_id = m->huff_buffer[i].table_id;
138         code = m->huff_buffer[i].code;
139         nbits = code & 0xf;
140 
141         put_bits(&s->pb, huff_size[table_id][code], huff_code[table_id][code]);
142         if (nbits != 0) {
143             put_sbits(&s->pb, nbits, m->huff_buffer[i].mant);
144         }
145     }
146 
147     m->huff_ncode = 0;
148     s->i_tex_bits = get_bits_diff(s);
149 }
150 
151 /**
152  * Builds all 4 optimal Huffman tables.
153  *
154  * Uses the data stored in the JPEG buffer to compute the tables.
155  * Stores the Huffman tables in the bits_* and val_* arrays in the MJpegContext.
156  *
157  * @param m MJpegContext containing the JPEG buffer.
158  */
mjpeg_build_optimal_huffman(MJpegContext * m)159 static void mjpeg_build_optimal_huffman(MJpegContext *m)
160 {
161     MJpegEncHuffmanContext dc_luminance_ctx;
162     MJpegEncHuffmanContext dc_chrominance_ctx;
163     MJpegEncHuffmanContext ac_luminance_ctx;
164     MJpegEncHuffmanContext ac_chrominance_ctx;
165     MJpegEncHuffmanContext *ctx[4] = { &dc_luminance_ctx,
166                                        &dc_chrominance_ctx,
167                                        &ac_luminance_ctx,
168                                        &ac_chrominance_ctx };
169     for (int i = 0; i < 4; i++)
170         ff_mjpeg_encode_huffman_init(ctx[i]);
171 
172     for (int i = 0; i < m->huff_ncode; i++) {
173         int table_id = m->huff_buffer[i].table_id;
174         int code     = m->huff_buffer[i].code;
175 
176         ff_mjpeg_encode_huffman_increment(ctx[table_id], code);
177     }
178 
179     ff_mjpeg_encode_huffman_close(&dc_luminance_ctx,
180                                   m->bits_dc_luminance,
181                                   m->val_dc_luminance, 12);
182     ff_mjpeg_encode_huffman_close(&dc_chrominance_ctx,
183                                   m->bits_dc_chrominance,
184                                   m->val_dc_chrominance, 12);
185     ff_mjpeg_encode_huffman_close(&ac_luminance_ctx,
186                                   m->bits_ac_luminance,
187                                   m->val_ac_luminance, 256);
188     ff_mjpeg_encode_huffman_close(&ac_chrominance_ctx,
189                                   m->bits_ac_chrominance,
190                                   m->val_ac_chrominance, 256);
191 
192     ff_mjpeg_build_huffman_codes(m->huff_size_dc_luminance,
193                                  m->huff_code_dc_luminance,
194                                  m->bits_dc_luminance,
195                                  m->val_dc_luminance);
196     ff_mjpeg_build_huffman_codes(m->huff_size_dc_chrominance,
197                                  m->huff_code_dc_chrominance,
198                                  m->bits_dc_chrominance,
199                                  m->val_dc_chrominance);
200     ff_mjpeg_build_huffman_codes(m->huff_size_ac_luminance,
201                                  m->huff_code_ac_luminance,
202                                  m->bits_ac_luminance,
203                                  m->val_ac_luminance);
204     ff_mjpeg_build_huffman_codes(m->huff_size_ac_chrominance,
205                                  m->huff_code_ac_chrominance,
206                                  m->bits_ac_chrominance,
207                                  m->val_ac_chrominance);
208 }
209 #endif
210 
211 /**
212  * Writes the complete JPEG frame when optimal huffman tables are enabled,
213  * otherwise writes the stuffing.
214  *
215  * Header + values + stuffing.
216  *
217  * @param s The MpegEncContext.
218  * @return int Error code, 0 if successful.
219  */
ff_mjpeg_encode_stuffing(MpegEncContext * s)220 int ff_mjpeg_encode_stuffing(MpegEncContext *s)
221 {
222     MJpegContext *const m = s->mjpeg_ctx;
223     PutBitContext *pbc = &s->pb;
224     int mb_y = s->mb_y - !s->mb_x;
225     int ret;
226 
227 #if CONFIG_MJPEG_ENCODER
228     if (m->huffman == HUFFMAN_TABLE_OPTIMAL) {
229 
230         mjpeg_build_optimal_huffman(m);
231 
232         // Replace the VLCs with the optimal ones.
233         // The default ones may be used for trellis during quantization.
234         init_uni_ac_vlc(m->huff_size_ac_luminance,   m->uni_ac_vlc_len);
235         init_uni_ac_vlc(m->huff_size_ac_chrominance, m->uni_chroma_ac_vlc_len);
236         s->intra_ac_vlc_length      =
237         s->intra_ac_vlc_last_length = m->uni_ac_vlc_len;
238         s->intra_chroma_ac_vlc_length      =
239         s->intra_chroma_ac_vlc_last_length = m->uni_chroma_ac_vlc_len;
240 
241         mjpeg_encode_picture_header(s);
242         mjpeg_encode_picture_frame(s);
243     }
244 #endif
245 
246     ret = ff_mpv_reallocate_putbitbuffer(s, put_bits_count(&s->pb) / 8 + 100,
247                                             put_bits_count(&s->pb) / 4 + 1000);
248     if (ret < 0) {
249         av_log(s->avctx, AV_LOG_ERROR, "Buffer reallocation failed\n");
250         goto fail;
251     }
252 
253     ff_mjpeg_escape_FF(pbc, s->esc_pos);
254 
255     if (s->slice_context_count > 1 && mb_y < s->mb_height - 1)
256         put_marker(pbc, RST0 + (mb_y&7));
257     s->esc_pos = put_bytes_count(pbc, 0);
258 
259 fail:
260     for (int i = 0; i < 3; i++)
261         s->last_dc[i] = 128 << s->intra_dc_precision;
262 
263     return ret;
264 }
265 
alloc_huffman(MpegEncContext * s)266 static int alloc_huffman(MpegEncContext *s)
267 {
268     MJpegContext *m = s->mjpeg_ctx;
269     size_t num_mbs, num_blocks, num_codes;
270     int blocks_per_mb;
271 
272     // We need to init this here as the mjpeg init is called before the common init,
273     s->mb_width  = (s->width  + 15) / 16;
274     s->mb_height = (s->height + 15) / 16;
275 
276     switch (s->chroma_format) {
277     case CHROMA_420: blocks_per_mb =  6; break;
278     case CHROMA_422: blocks_per_mb =  8; break;
279     case CHROMA_444: blocks_per_mb = 12; break;
280     default: av_assert0(0);
281     };
282 
283     // Make sure we have enough space to hold this frame.
284     num_mbs = s->mb_width * s->mb_height;
285     num_blocks = num_mbs * blocks_per_mb;
286     num_codes = num_blocks * 64;
287 
288     m->huff_buffer = av_malloc_array(num_codes, sizeof(MJpegHuffmanCode));
289     if (!m->huff_buffer)
290         return AVERROR(ENOMEM);
291     return 0;
292 }
293 
ff_mjpeg_encode_init(MpegEncContext * s)294 av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
295 {
296     MJpegContext *const m = &((MJPEGEncContext*)s)->mjpeg;
297     int ret, use_slices;
298 
299     s->mjpeg_ctx = m;
300     use_slices = s->avctx->slices > 0 ? s->avctx->slices > 1 :
301                  (s->avctx->active_thread_type & FF_THREAD_SLICE) &&
302                  s->avctx->thread_count > 1;
303 
304     if (s->codec_id == AV_CODEC_ID_AMV || use_slices)
305         m->huffman = HUFFMAN_TABLE_DEFAULT;
306 
307     if (s->mpv_flags & FF_MPV_FLAG_QP_RD) {
308         // Used to produce garbage with MJPEG.
309         av_log(s->avctx, AV_LOG_ERROR,
310                "QP RD is no longer compatible with MJPEG or AMV\n");
311         return AVERROR(EINVAL);
312     }
313 
314     /* The following check is automatically true for AMV,
315      * but it doesn't hurt either. */
316     ret = ff_mjpeg_encode_check_pix_fmt(s->avctx);
317     if (ret < 0)
318         return ret;
319 
320     if (s->width > 65500 || s->height > 65500) {
321         av_log(s, AV_LOG_ERROR, "JPEG does not support resolutions above 65500x65500\n");
322         return AVERROR(EINVAL);
323     }
324 
325     s->min_qcoeff=-1023;
326     s->max_qcoeff= 1023;
327 
328     // Build default Huffman tables.
329     // These may be overwritten later with more optimal Huffman tables, but
330     // they are needed at least right now for some processes like trellis.
331     ff_mjpeg_build_huffman_codes(m->huff_size_dc_luminance,
332                                  m->huff_code_dc_luminance,
333                                  ff_mjpeg_bits_dc_luminance,
334                                  ff_mjpeg_val_dc);
335     ff_mjpeg_build_huffman_codes(m->huff_size_dc_chrominance,
336                                  m->huff_code_dc_chrominance,
337                                  ff_mjpeg_bits_dc_chrominance,
338                                  ff_mjpeg_val_dc);
339     ff_mjpeg_build_huffman_codes(m->huff_size_ac_luminance,
340                                  m->huff_code_ac_luminance,
341                                  ff_mjpeg_bits_ac_luminance,
342                                  ff_mjpeg_val_ac_luminance);
343     ff_mjpeg_build_huffman_codes(m->huff_size_ac_chrominance,
344                                  m->huff_code_ac_chrominance,
345                                  ff_mjpeg_bits_ac_chrominance,
346                                  ff_mjpeg_val_ac_chrominance);
347 
348     init_uni_ac_vlc(m->huff_size_ac_luminance,   m->uni_ac_vlc_len);
349     init_uni_ac_vlc(m->huff_size_ac_chrominance, m->uni_chroma_ac_vlc_len);
350     s->intra_ac_vlc_length      =
351     s->intra_ac_vlc_last_length = m->uni_ac_vlc_len;
352     s->intra_chroma_ac_vlc_length      =
353     s->intra_chroma_ac_vlc_last_length = m->uni_chroma_ac_vlc_len;
354 
355     // Buffers start out empty.
356     m->huff_ncode = 0;
357 
358     if (m->huffman == HUFFMAN_TABLE_OPTIMAL)
359         return alloc_huffman(s);
360 
361     return 0;
362 }
363 
mjpeg_encode_close(AVCodecContext * avctx)364 static av_cold int mjpeg_encode_close(AVCodecContext *avctx)
365 {
366     MJPEGEncContext *const mjpeg = avctx->priv_data;
367     av_freep(&mjpeg->mjpeg.huff_buffer);
368     ff_mpv_encode_end(avctx);
369     return 0;
370 }
371 
372 /**
373  * Add code and table_id to the JPEG buffer.
374  *
375  * @param s The MJpegContext which contains the JPEG buffer.
376  * @param table_id Which Huffman table the code belongs to.
377  * @param code The encoded exponent of the coefficients and the run-bits.
378  */
ff_mjpeg_encode_code(MJpegContext * s,uint8_t table_id,int code)379 static inline void ff_mjpeg_encode_code(MJpegContext *s, uint8_t table_id, int code)
380 {
381     MJpegHuffmanCode *c = &s->huff_buffer[s->huff_ncode++];
382     c->table_id = table_id;
383     c->code = code;
384 }
385 
386 /**
387  * Add the coefficient's data to the JPEG buffer.
388  *
389  * @param s The MJpegContext which contains the JPEG buffer.
390  * @param table_id Which Huffman table the code belongs to.
391  * @param val The coefficient.
392  * @param run The run-bits.
393  */
ff_mjpeg_encode_coef(MJpegContext * s,uint8_t table_id,int val,int run)394 static void ff_mjpeg_encode_coef(MJpegContext *s, uint8_t table_id, int val, int run)
395 {
396     int mant, code;
397 
398     if (val == 0) {
399         av_assert0(run == 0);
400         ff_mjpeg_encode_code(s, table_id, 0);
401     } else {
402         mant = val;
403         if (val < 0) {
404             val = -val;
405             mant--;
406         }
407 
408         code = (run << 4) | (av_log2_16bit(val) + 1);
409 
410         s->huff_buffer[s->huff_ncode].mant = mant;
411         ff_mjpeg_encode_code(s, table_id, code);
412     }
413 }
414 
415 /**
416  * Add the block's data into the JPEG buffer.
417  *
418  * @param s The MpegEncContext that contains the JPEG buffer.
419  * @param block The block.
420  * @param n The block's index or number.
421  */
record_block(MpegEncContext * s,int16_t * block,int n)422 static void record_block(MpegEncContext *s, int16_t *block, int n)
423 {
424     int i, j, table_id;
425     int component, dc, last_index, val, run;
426     MJpegContext *m = s->mjpeg_ctx;
427 
428     /* DC coef */
429     component = (n <= 3 ? 0 : (n&1) + 1);
430     table_id = (n <= 3 ? 0 : 1);
431     dc = block[0]; /* overflow is impossible */
432     val = dc - s->last_dc[component];
433 
434     ff_mjpeg_encode_coef(m, table_id, val, 0);
435 
436     s->last_dc[component] = dc;
437 
438     /* AC coefs */
439 
440     run = 0;
441     last_index = s->block_last_index[n];
442     table_id |= 2;
443 
444     for(i=1;i<=last_index;i++) {
445         j = s->intra_scantable.permutated[i];
446         val = block[j];
447 
448         if (val == 0) {
449             run++;
450         } else {
451             while (run >= 16) {
452                 ff_mjpeg_encode_code(m, table_id, 0xf0);
453                 run -= 16;
454             }
455             ff_mjpeg_encode_coef(m, table_id, val, run);
456             run = 0;
457         }
458     }
459 
460     /* output EOB only if not already 64 values */
461     if (last_index < 63 || run != 0)
462         ff_mjpeg_encode_code(m, table_id, 0);
463 }
464 
encode_block(MpegEncContext * s,int16_t * block,int n)465 static void encode_block(MpegEncContext *s, int16_t *block, int n)
466 {
467     int mant, nbits, code, i, j;
468     int component, dc, run, last_index, val;
469     MJpegContext *m = s->mjpeg_ctx;
470     uint8_t *huff_size_ac;
471     uint16_t *huff_code_ac;
472 
473     /* DC coef */
474     component = (n <= 3 ? 0 : (n&1) + 1);
475     dc = block[0]; /* overflow is impossible */
476     val = dc - s->last_dc[component];
477     if (n < 4) {
478         ff_mjpeg_encode_dc(&s->pb, val, m->huff_size_dc_luminance, m->huff_code_dc_luminance);
479         huff_size_ac = m->huff_size_ac_luminance;
480         huff_code_ac = m->huff_code_ac_luminance;
481     } else {
482         ff_mjpeg_encode_dc(&s->pb, val, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
483         huff_size_ac = m->huff_size_ac_chrominance;
484         huff_code_ac = m->huff_code_ac_chrominance;
485     }
486     s->last_dc[component] = dc;
487 
488     /* AC coefs */
489 
490     run = 0;
491     last_index = s->block_last_index[n];
492     for(i=1;i<=last_index;i++) {
493         j = s->intra_scantable.permutated[i];
494         val = block[j];
495         if (val == 0) {
496             run++;
497         } else {
498             while (run >= 16) {
499                 put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);
500                 run -= 16;
501             }
502             mant = val;
503             if (val < 0) {
504                 val = -val;
505                 mant--;
506             }
507 
508             nbits= av_log2_16bit(val) + 1;
509             code = (run << 4) | nbits;
510 
511             put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);
512 
513             put_sbits(&s->pb, nbits, mant);
514             run = 0;
515         }
516     }
517 
518     /* output EOB only if not already 64 values */
519     if (last_index < 63 || run != 0)
520         put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
521 }
522 
ff_mjpeg_encode_mb(MpegEncContext * s,int16_t block[12][64])523 void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[12][64])
524 {
525     int i;
526     if (s->mjpeg_ctx->huffman == HUFFMAN_TABLE_OPTIMAL) {
527         if (s->chroma_format == CHROMA_444) {
528             record_block(s, block[0], 0);
529             record_block(s, block[2], 2);
530             record_block(s, block[4], 4);
531             record_block(s, block[8], 8);
532             record_block(s, block[5], 5);
533             record_block(s, block[9], 9);
534 
535             if (16*s->mb_x+8 < s->width) {
536                 record_block(s, block[1], 1);
537                 record_block(s, block[3], 3);
538                 record_block(s, block[6], 6);
539                 record_block(s, block[10], 10);
540                 record_block(s, block[7], 7);
541                 record_block(s, block[11], 11);
542             }
543         } else {
544             for(i=0;i<5;i++) {
545                 record_block(s, block[i], i);
546             }
547             if (s->chroma_format == CHROMA_420) {
548                 record_block(s, block[5], 5);
549             } else {
550                 record_block(s, block[6], 6);
551                 record_block(s, block[5], 5);
552                 record_block(s, block[7], 7);
553             }
554         }
555     } else {
556         if (s->chroma_format == CHROMA_444) {
557             encode_block(s, block[0], 0);
558             encode_block(s, block[2], 2);
559             encode_block(s, block[4], 4);
560             encode_block(s, block[8], 8);
561             encode_block(s, block[5], 5);
562             encode_block(s, block[9], 9);
563 
564             if (16*s->mb_x+8 < s->width) {
565                 encode_block(s, block[1], 1);
566                 encode_block(s, block[3], 3);
567                 encode_block(s, block[6], 6);
568                 encode_block(s, block[10], 10);
569                 encode_block(s, block[7], 7);
570                 encode_block(s, block[11], 11);
571             }
572         } else {
573             for(i=0;i<5;i++) {
574                 encode_block(s, block[i], i);
575             }
576             if (s->chroma_format == CHROMA_420) {
577                 encode_block(s, block[5], 5);
578             } else {
579                 encode_block(s, block[6], 6);
580                 encode_block(s, block[5], 5);
581                 encode_block(s, block[7], 7);
582             }
583         }
584 
585         s->i_tex_bits += get_bits_diff(s);
586     }
587 }
588 
589 #if CONFIG_AMV_ENCODER
590 // maximum over s->mjpeg_vsample[i]
591 #define V_MAX 2
amv_encode_picture(AVCodecContext * avctx,AVPacket * pkt,const AVFrame * pic_arg,int * got_packet)592 static int amv_encode_picture(AVCodecContext *avctx, AVPacket *pkt,
593                               const AVFrame *pic_arg, int *got_packet)
594 {
595     MpegEncContext *s = avctx->priv_data;
596     AVFrame *pic;
597     int i, ret;
598     int chroma_h_shift, chroma_v_shift;
599 
600     av_pix_fmt_get_chroma_sub_sample(avctx->pix_fmt, &chroma_h_shift, &chroma_v_shift);
601 
602     if ((avctx->height & 15) && avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {
603         av_log(avctx, AV_LOG_ERROR,
604                "Heights which are not a multiple of 16 might fail with some decoders, "
605                "use vstrict=-1 / -strict -1 to use %d anyway.\n", avctx->height);
606         av_log(avctx, AV_LOG_WARNING, "If you have a device that plays AMV videos, please test if videos "
607                "with such heights work with it and report your findings to ffmpeg-devel@ffmpeg.org\n");
608         return AVERROR_EXPERIMENTAL;
609     }
610 
611     pic = av_frame_clone(pic_arg);
612     if (!pic)
613         return AVERROR(ENOMEM);
614     //picture should be flipped upside-down
615     for(i=0; i < 3; i++) {
616         int vsample = i ? 2 >> chroma_v_shift : 2;
617         pic->data[i] += pic->linesize[i] * (vsample * s->height / V_MAX - 1);
618         pic->linesize[i] *= -1;
619     }
620     ret = ff_mpv_encode_picture(avctx, pkt, pic, got_packet);
621     av_frame_free(&pic);
622     return ret;
623 }
624 #endif
625 
626 #define OFFSET(x) offsetof(MJPEGEncContext, mjpeg.x)
627 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
628 static const AVOption options[] = {
629 FF_MPV_COMMON_OPTS
630 { "huffman", "Huffman table strategy", OFFSET(huffman), AV_OPT_TYPE_INT, { .i64 = HUFFMAN_TABLE_OPTIMAL }, 0, NB_HUFFMAN_TABLE_OPTION - 1, VE, "huffman" },
631     { "default", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = HUFFMAN_TABLE_DEFAULT }, INT_MIN, INT_MAX, VE, "huffman" },
632     { "optimal", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = HUFFMAN_TABLE_OPTIMAL }, INT_MIN, INT_MAX, VE, "huffman" },
633 { "force_duplicated_matrix", "Always write luma and chroma matrix for mjpeg, useful for rtp streaming.", OFFSET(force_duplicated_matrix), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, VE },
634 { NULL},
635 };
636 
637 #if CONFIG_MJPEG_ENCODER
638 static const AVClass mjpeg_class = {
639     .class_name = "mjpeg encoder",
640     .item_name  = av_default_item_name,
641     .option     = options,
642     .version    = LIBAVUTIL_VERSION_INT,
643 };
644 
645 const FFCodec ff_mjpeg_encoder = {
646     .p.name         = "mjpeg",
647     .p.long_name    = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
648     .p.type         = AVMEDIA_TYPE_VIDEO,
649     .p.id           = AV_CODEC_ID_MJPEG,
650     .priv_data_size = sizeof(MJPEGEncContext),
651     .init           = ff_mpv_encode_init,
652     FF_CODEC_ENCODE_CB(ff_mpv_encode_picture),
653     .close          = mjpeg_encode_close,
654     .p.capabilities = AV_CODEC_CAP_SLICE_THREADS | AV_CODEC_CAP_FRAME_THREADS,
655     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
656     .p.pix_fmts     = (const enum AVPixelFormat[]) {
657         AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P,
658         AV_PIX_FMT_YUV420P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV444P,
659         AV_PIX_FMT_NONE
660     },
661     .p.priv_class   = &mjpeg_class,
662     .p.profiles     = NULL_IF_CONFIG_SMALL(ff_mjpeg_profiles),
663 };
664 #endif
665 
666 #if CONFIG_AMV_ENCODER
667 static const AVClass amv_class = {
668     .class_name = "amv encoder",
669     .item_name  = av_default_item_name,
670     .option     = options,
671     .version    = LIBAVUTIL_VERSION_INT,
672 };
673 
674 const FFCodec ff_amv_encoder = {
675     .p.name         = "amv",
676     .p.long_name    = NULL_IF_CONFIG_SMALL("AMV Video"),
677     .p.type         = AVMEDIA_TYPE_VIDEO,
678     .p.id           = AV_CODEC_ID_AMV,
679     .priv_data_size = sizeof(MJPEGEncContext),
680     .init           = ff_mpv_encode_init,
681     FF_CODEC_ENCODE_CB(amv_encode_picture),
682     .close          = mjpeg_encode_close,
683     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
684     .p.pix_fmts     = (const enum AVPixelFormat[]) {
685         AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_NONE
686     },
687     .p.priv_class   = &amv_class,
688 };
689 #endif
690