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//#define DEBUG
34#include <assert.h>
35
36#include "avcodec.h"
37#include "dsputil.h"
38#include "mpegvideo.h"
39#include "mjpeg.h"
40#include "mjpegenc.h"
41
42/* use two quantizer tables (one for luminance and one for chrominance) */
43/* not yet working */
44#undef TWOMATRIXES
45
46
47av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
48{
49    MJpegContext *m;
50
51    m = av_malloc(sizeof(MJpegContext));
52    if (!m)
53        return -1;
54
55    s->min_qcoeff=-1023;
56    s->max_qcoeff= 1023;
57
58    /* build all the huffman tables */
59    ff_mjpeg_build_huffman_codes(m->huff_size_dc_luminance,
60                                 m->huff_code_dc_luminance,
61                                 ff_mjpeg_bits_dc_luminance,
62                                 ff_mjpeg_val_dc);
63    ff_mjpeg_build_huffman_codes(m->huff_size_dc_chrominance,
64                                 m->huff_code_dc_chrominance,
65                                 ff_mjpeg_bits_dc_chrominance,
66                                 ff_mjpeg_val_dc);
67    ff_mjpeg_build_huffman_codes(m->huff_size_ac_luminance,
68                                 m->huff_code_ac_luminance,
69                                 ff_mjpeg_bits_ac_luminance,
70                                 ff_mjpeg_val_ac_luminance);
71    ff_mjpeg_build_huffman_codes(m->huff_size_ac_chrominance,
72                                 m->huff_code_ac_chrominance,
73                                 ff_mjpeg_bits_ac_chrominance,
74                                 ff_mjpeg_val_ac_chrominance);
75
76    s->mjpeg_ctx = m;
77    return 0;
78}
79
80void ff_mjpeg_encode_close(MpegEncContext *s)
81{
82    av_free(s->mjpeg_ctx);
83}
84
85/* table_class: 0 = DC coef, 1 = AC coefs */
86static int put_huffman_table(MpegEncContext *s, int table_class, int table_id,
87                             const uint8_t *bits_table, const uint8_t *value_table)
88{
89    PutBitContext *p = &s->pb;
90    int n, i;
91
92    put_bits(p, 4, table_class);
93    put_bits(p, 4, table_id);
94
95    n = 0;
96    for(i=1;i<=16;i++) {
97        n += bits_table[i];
98        put_bits(p, 8, bits_table[i]);
99    }
100
101    for(i=0;i<n;i++)
102        put_bits(p, 8, value_table[i]);
103
104    return n + 17;
105}
106
107static void jpeg_table_header(MpegEncContext *s)
108{
109    PutBitContext *p = &s->pb;
110    int i, j, size;
111    uint8_t *ptr;
112
113    /* quant matrixes */
114    put_marker(p, DQT);
115#ifdef TWOMATRIXES
116    put_bits(p, 16, 2 + 2 * (1 + 64));
117#else
118    put_bits(p, 16, 2 + 1 * (1 + 64));
119#endif
120    put_bits(p, 4, 0); /* 8 bit precision */
121    put_bits(p, 4, 0); /* table 0 */
122    for(i=0;i<64;i++) {
123        j = s->intra_scantable.permutated[i];
124        put_bits(p, 8, s->intra_matrix[j]);
125    }
126#ifdef TWOMATRIXES
127    put_bits(p, 4, 0); /* 8 bit precision */
128    put_bits(p, 4, 1); /* table 1 */
129    for(i=0;i<64;i++) {
130        j = s->intra_scantable.permutated[i];
131        put_bits(p, 8, s->chroma_intra_matrix[j]);
132    }
133#endif
134
135    /* huffman table */
136    put_marker(p, DHT);
137    flush_put_bits(p);
138    ptr = put_bits_ptr(p);
139    put_bits(p, 16, 0); /* patched later */
140    size = 2;
141    size += put_huffman_table(s, 0, 0, ff_mjpeg_bits_dc_luminance,
142                              ff_mjpeg_val_dc);
143    size += put_huffman_table(s, 0, 1, ff_mjpeg_bits_dc_chrominance,
144                              ff_mjpeg_val_dc);
145
146    size += put_huffman_table(s, 1, 0, ff_mjpeg_bits_ac_luminance,
147                              ff_mjpeg_val_ac_luminance);
148    size += put_huffman_table(s, 1, 1, ff_mjpeg_bits_ac_chrominance,
149                              ff_mjpeg_val_ac_chrominance);
150    AV_WB16(ptr, size);
151}
152
153static void jpeg_put_comments(MpegEncContext *s)
154{
155    PutBitContext *p = &s->pb;
156    int size;
157    uint8_t *ptr;
158
159    if (s->aspect_ratio_info /* && !lossless */)
160    {
161    /* JFIF header */
162    put_marker(p, APP0);
163    put_bits(p, 16, 16);
164    ff_put_string(p, "JFIF", 1); /* this puts the trailing zero-byte too */
165    put_bits(p, 16, 0x0201); /* v 1.02 */
166    put_bits(p, 8, 0); /* units type: 0 - aspect ratio */
167    put_bits(p, 16, s->avctx->sample_aspect_ratio.num);
168    put_bits(p, 16, s->avctx->sample_aspect_ratio.den);
169    put_bits(p, 8, 0); /* thumbnail width */
170    put_bits(p, 8, 0); /* thumbnail height */
171    }
172
173    /* comment */
174    if(!(s->flags & CODEC_FLAG_BITEXACT)){
175        put_marker(p, COM);
176        flush_put_bits(p);
177        ptr = put_bits_ptr(p);
178        put_bits(p, 16, 0); /* patched later */
179        ff_put_string(p, LIBAVCODEC_IDENT, 1);
180        size = strlen(LIBAVCODEC_IDENT)+3;
181        AV_WB16(ptr, size);
182    }
183
184    if(  s->avctx->pix_fmt == PIX_FMT_YUV420P
185       ||s->avctx->pix_fmt == PIX_FMT_YUV422P
186       ||s->avctx->pix_fmt == PIX_FMT_YUV444P){
187        put_marker(p, COM);
188        flush_put_bits(p);
189        ptr = put_bits_ptr(p);
190        put_bits(p, 16, 0); /* patched later */
191        ff_put_string(p, "CS=ITU601", 1);
192        size = strlen("CS=ITU601")+3;
193        AV_WB16(ptr, size);
194    }
195}
196
197void ff_mjpeg_encode_picture_header(MpegEncContext *s)
198{
199    const int lossless= s->avctx->codec_id != CODEC_ID_MJPEG;
200
201    put_marker(&s->pb, SOI);
202
203    jpeg_put_comments(s);
204
205    jpeg_table_header(s);
206
207    switch(s->avctx->codec_id){
208    case CODEC_ID_MJPEG:  put_marker(&s->pb, SOF0 ); break;
209    case CODEC_ID_LJPEG:  put_marker(&s->pb, SOF3 ); break;
210    default: assert(0);
211    }
212
213    put_bits(&s->pb, 16, 17);
214    if(lossless && s->avctx->pix_fmt == PIX_FMT_BGRA)
215        put_bits(&s->pb, 8, 9); /* 9 bits/component RCT */
216    else
217        put_bits(&s->pb, 8, 8); /* 8 bits/component */
218    put_bits(&s->pb, 16, s->height);
219    put_bits(&s->pb, 16, s->width);
220    put_bits(&s->pb, 8, 3); /* 3 components */
221
222    /* Y component */
223    put_bits(&s->pb, 8, 1); /* component number */
224    put_bits(&s->pb, 4, s->mjpeg_hsample[0]); /* H factor */
225    put_bits(&s->pb, 4, s->mjpeg_vsample[0]); /* V factor */
226    put_bits(&s->pb, 8, 0); /* select matrix */
227
228    /* Cb component */
229    put_bits(&s->pb, 8, 2); /* component number */
230    put_bits(&s->pb, 4, s->mjpeg_hsample[1]); /* H factor */
231    put_bits(&s->pb, 4, s->mjpeg_vsample[1]); /* V factor */
232#ifdef TWOMATRIXES
233    put_bits(&s->pb, 8, lossless ? 0 : 1); /* select matrix */
234#else
235    put_bits(&s->pb, 8, 0); /* select matrix */
236#endif
237
238    /* Cr component */
239    put_bits(&s->pb, 8, 3); /* component number */
240    put_bits(&s->pb, 4, s->mjpeg_hsample[2]); /* H factor */
241    put_bits(&s->pb, 4, s->mjpeg_vsample[2]); /* V factor */
242#ifdef TWOMATRIXES
243    put_bits(&s->pb, 8, lossless ? 0 : 1); /* select matrix */
244#else
245    put_bits(&s->pb, 8, 0); /* select matrix */
246#endif
247
248    /* scan header */
249    put_marker(&s->pb, SOS);
250    put_bits(&s->pb, 16, 12); /* length */
251    put_bits(&s->pb, 8, 3); /* 3 components */
252
253    /* Y component */
254    put_bits(&s->pb, 8, 1); /* index */
255    put_bits(&s->pb, 4, 0); /* DC huffman table index */
256    put_bits(&s->pb, 4, 0); /* AC huffman table index */
257
258    /* Cb component */
259    put_bits(&s->pb, 8, 2); /* index */
260    put_bits(&s->pb, 4, 1); /* DC huffman table index */
261    put_bits(&s->pb, 4, lossless ? 0 : 1); /* AC huffman table index */
262
263    /* Cr component */
264    put_bits(&s->pb, 8, 3); /* index */
265    put_bits(&s->pb, 4, 1); /* DC huffman table index */
266    put_bits(&s->pb, 4, lossless ? 0 : 1); /* AC huffman table index */
267
268    put_bits(&s->pb, 8, lossless ? s->avctx->prediction_method+1 : 0); /* Ss (not used) */
269
270    switch(s->avctx->codec_id){
271    case CODEC_ID_MJPEG:  put_bits(&s->pb, 8, 63); break; /* Se (not used) */
272    case CODEC_ID_LJPEG:  put_bits(&s->pb, 8,  0); break; /* not used */
273    default: assert(0);
274    }
275
276    put_bits(&s->pb, 8, 0); /* Ah/Al (not used) */
277}
278
279static void escape_FF(MpegEncContext *s, int start)
280{
281    int size= put_bits_count(&s->pb) - start*8;
282    int i, ff_count;
283    uint8_t *buf= s->pb.buf + start;
284    int align= (-(size_t)(buf))&3;
285
286    assert((size&7) == 0);
287    size >>= 3;
288
289    ff_count=0;
290    for(i=0; i<size && i<align; i++){
291        if(buf[i]==0xFF) ff_count++;
292    }
293    for(; i<size-15; i+=16){
294        int acc, v;
295
296        v= *(uint32_t*)(&buf[i]);
297        acc= (((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
298        v= *(uint32_t*)(&buf[i+4]);
299        acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
300        v= *(uint32_t*)(&buf[i+8]);
301        acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
302        v= *(uint32_t*)(&buf[i+12]);
303        acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;
304
305        acc>>=4;
306        acc+= (acc>>16);
307        acc+= (acc>>8);
308        ff_count+= acc&0xFF;
309    }
310    for(; i<size; i++){
311        if(buf[i]==0xFF) ff_count++;
312    }
313
314    if(ff_count==0) return;
315
316    flush_put_bits(&s->pb);
317    skip_put_bytes(&s->pb, ff_count);
318
319    for(i=size-1; ff_count; i--){
320        int v= buf[i];
321
322        if(v==0xFF){
323//printf("%d %d\n", i, ff_count);
324            buf[i+ff_count]= 0;
325            ff_count--;
326        }
327
328        buf[i+ff_count]= v;
329    }
330}
331
332void ff_mjpeg_encode_stuffing(PutBitContext * pbc)
333{
334    int length;
335    length= (-put_bits_count(pbc))&7;
336    if(length) put_bits(pbc, length, (1<<length)-1);
337}
338
339void ff_mjpeg_encode_picture_trailer(MpegEncContext *s)
340{
341    ff_mjpeg_encode_stuffing(&s->pb);
342    flush_put_bits(&s->pb);
343
344    assert((s->header_bits&7)==0);
345
346    escape_FF(s, s->header_bits>>3);
347
348    put_marker(&s->pb, EOI);
349}
350
351void ff_mjpeg_encode_dc(MpegEncContext *s, int val,
352                        uint8_t *huff_size, uint16_t *huff_code)
353{
354    int mant, nbits;
355
356    if (val == 0) {
357        put_bits(&s->pb, huff_size[0], huff_code[0]);
358    } else {
359        mant = val;
360        if (val < 0) {
361            val = -val;
362            mant--;
363        }
364
365        nbits= av_log2_16bit(val) + 1;
366
367        put_bits(&s->pb, huff_size[nbits], huff_code[nbits]);
368
369        put_sbits(&s->pb, nbits, mant);
370    }
371}
372
373static void encode_block(MpegEncContext *s, DCTELEM *block, int n)
374{
375    int mant, nbits, code, i, j;
376    int component, dc, run, last_index, val;
377    MJpegContext *m = s->mjpeg_ctx;
378    uint8_t *huff_size_ac;
379    uint16_t *huff_code_ac;
380
381    /* DC coef */
382    component = (n <= 3 ? 0 : (n&1) + 1);
383    dc = block[0]; /* overflow is impossible */
384    val = dc - s->last_dc[component];
385    if (n < 4) {
386        ff_mjpeg_encode_dc(s, val, m->huff_size_dc_luminance, m->huff_code_dc_luminance);
387        huff_size_ac = m->huff_size_ac_luminance;
388        huff_code_ac = m->huff_code_ac_luminance;
389    } else {
390        ff_mjpeg_encode_dc(s, val, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
391        huff_size_ac = m->huff_size_ac_chrominance;
392        huff_code_ac = m->huff_code_ac_chrominance;
393    }
394    s->last_dc[component] = dc;
395
396    /* AC coefs */
397
398    run = 0;
399    last_index = s->block_last_index[n];
400    for(i=1;i<=last_index;i++) {
401        j = s->intra_scantable.permutated[i];
402        val = block[j];
403        if (val == 0) {
404            run++;
405        } else {
406            while (run >= 16) {
407                put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);
408                run -= 16;
409            }
410            mant = val;
411            if (val < 0) {
412                val = -val;
413                mant--;
414            }
415
416            nbits= av_log2(val) + 1;
417            code = (run << 4) | nbits;
418
419            put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);
420
421            put_sbits(&s->pb, nbits, mant);
422            run = 0;
423        }
424    }
425
426    /* output EOB only if not already 64 values */
427    if (last_index < 63 || run != 0)
428        put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
429}
430
431void ff_mjpeg_encode_mb(MpegEncContext *s, DCTELEM block[6][64])
432{
433    int i;
434    for(i=0;i<5;i++) {
435        encode_block(s, block[i], i);
436    }
437    if (s->chroma_format == CHROMA_420) {
438        encode_block(s, block[5], 5);
439    } else {
440        encode_block(s, block[6], 6);
441        encode_block(s, block[5], 5);
442        encode_block(s, block[7], 7);
443    }
444}
445
446AVCodec mjpeg_encoder = {
447    "mjpeg",
448    AVMEDIA_TYPE_VIDEO,
449    CODEC_ID_MJPEG,
450    sizeof(MpegEncContext),
451    MPV_encode_init,
452    MPV_encode_picture,
453    MPV_encode_end,
454    .pix_fmts= (const enum PixelFormat[]){PIX_FMT_YUVJ420P, PIX_FMT_YUVJ422P, PIX_FMT_NONE},
455    .long_name= NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
456};
457