3 * Copyright (c) 2000, 2001 Fabrice Bellard
4 * Copyright (c) 2003 Alex Beregszaszi
5 * Copyright (c) 2003-2004 Michael Niedermayer
7 * Support for external huffman table, various fixes (AVID workaround),
8 * aspecting, new decode_frame mechanism and apple mjpeg-b support
11 * This file is part of Libav.
13 * Libav 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.
18 * Libav 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.
23 * You should have received a copy of the GNU Lesser General Public
24 * License along with Libav; if not, write to the Free Software
25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
35 #include "libavutil/pixdesc.h"
38 #include "mjpegenc_common.h"
39 #include "mpegvideo.h"
43 av_cold int ff_mjpeg_encode_init(MpegEncContext *s)
47 m = av_malloc(sizeof(MJpegContext));
49 return AVERROR(ENOMEM);
54 /* build all the huffman tables */
55 ff_mjpeg_build_huffman_codes(m->huff_size_dc_luminance,
56 m->huff_code_dc_luminance,
57 avpriv_mjpeg_bits_dc_luminance,
59 ff_mjpeg_build_huffman_codes(m->huff_size_dc_chrominance,
60 m->huff_code_dc_chrominance,
61 avpriv_mjpeg_bits_dc_chrominance,
63 ff_mjpeg_build_huffman_codes(m->huff_size_ac_luminance,
64 m->huff_code_ac_luminance,
65 avpriv_mjpeg_bits_ac_luminance,
66 avpriv_mjpeg_val_ac_luminance);
67 ff_mjpeg_build_huffman_codes(m->huff_size_ac_chrominance,
68 m->huff_code_ac_chrominance,
69 avpriv_mjpeg_bits_ac_chrominance,
70 avpriv_mjpeg_val_ac_chrominance);
76 void ff_mjpeg_encode_close(MpegEncContext *s)
78 av_free(s->mjpeg_ctx);
81 static void encode_block(MpegEncContext *s, int16_t *block, int n)
83 int mant, nbits, code, i, j;
84 int component, dc, run, last_index, val;
85 MJpegContext *m = s->mjpeg_ctx;
86 uint8_t *huff_size_ac;
87 uint16_t *huff_code_ac;
90 component = (n <= 3 ? 0 : (n&1) + 1);
91 dc = block[0]; /* overflow is impossible */
92 val = dc - s->last_dc[component];
94 ff_mjpeg_encode_dc(&s->pb, val, m->huff_size_dc_luminance, m->huff_code_dc_luminance);
95 huff_size_ac = m->huff_size_ac_luminance;
96 huff_code_ac = m->huff_code_ac_luminance;
98 ff_mjpeg_encode_dc(&s->pb, val, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
99 huff_size_ac = m->huff_size_ac_chrominance;
100 huff_code_ac = m->huff_code_ac_chrominance;
102 s->last_dc[component] = dc;
107 last_index = s->block_last_index[n];
108 for(i=1;i<=last_index;i++) {
109 j = s->intra_scantable.permutated[i];
115 put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);
124 nbits= av_log2(val) + 1;
125 code = (run << 4) | nbits;
127 put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);
129 put_sbits(&s->pb, nbits, mant);
134 /* output EOB only if not already 64 values */
135 if (last_index < 63 || run != 0)
136 put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
139 void ff_mjpeg_encode_mb(MpegEncContext *s, int16_t block[8][64])
143 encode_block(s, block[i], i);
145 if (s->chroma_format == CHROMA_420) {
146 encode_block(s, block[5], 5);
148 encode_block(s, block[6], 6);
149 encode_block(s, block[5], 5);
150 encode_block(s, block[7], 7);
153 s->i_tex_bits += get_bits_diff(s);
156 AVCodec ff_mjpeg_encoder = {
158 .long_name = NULL_IF_CONFIG_SMALL("MJPEG (Motion JPEG)"),
159 .type = AVMEDIA_TYPE_VIDEO,
160 .id = AV_CODEC_ID_MJPEG,
161 .priv_data_size = sizeof(MpegEncContext),
162 .init = ff_mpv_encode_init,
163 .encode2 = ff_mpv_encode_picture,
164 .close = ff_mpv_encode_end,
165 .pix_fmts = (const enum AVPixelFormat[]){
166 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_NONE