Clarify/simplify documentation for the default_val field in AVOption.
[FFMpeg-mirror/DVCPRO-HD.git] / libavcodec / ljpegenc.c
blob7ac013e3fae0ec8fd2689412eb1fd37cc16a0cdf
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
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
11 * This file is part of FFmpeg.
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.
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.
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
28 /**
29 * @file ljpegenc.c
30 * lossless JPEG encoder.
33 #include "avcodec.h"
34 #include "dsputil.h"
35 #include "mpegvideo.h"
36 #include "mjpeg.h"
37 #include "mjpegenc.h"
40 static int encode_picture_lossless(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){
41 MpegEncContext * const s = avctx->priv_data;
42 MJpegContext * const m = s->mjpeg_ctx;
43 AVFrame *pict = data;
44 const int width= s->width;
45 const int height= s->height;
46 AVFrame * const p= (AVFrame*)&s->current_picture;
47 const int predictor= avctx->prediction_method+1;
49 init_put_bits(&s->pb, buf, buf_size);
51 *p = *pict;
52 p->pict_type= FF_I_TYPE;
53 p->key_frame= 1;
55 ff_mjpeg_encode_picture_header(s);
57 s->header_bits= put_bits_count(&s->pb);
59 if(avctx->pix_fmt == PIX_FMT_RGB32){
60 int x, y, i;
61 const int linesize= p->linesize[0];
62 uint16_t (*buffer)[4]= (void *) s->rd_scratchpad;
63 int left[3], top[3], topleft[3];
65 for(i=0; i<3; i++){
66 buffer[0][i]= 1 << (9 - 1);
69 for(y = 0; y < height; y++) {
70 const int modified_predictor= y ? predictor : 1;
71 uint8_t *ptr = p->data[0] + (linesize * y);
73 if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < width*3*4){
74 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
75 return -1;
78 for(i=0; i<3; i++){
79 top[i]= left[i]= topleft[i]= buffer[0][i];
81 for(x = 0; x < width; x++) {
82 buffer[x][1] = ptr[4*x+0] - ptr[4*x+1] + 0x100;
83 buffer[x][2] = ptr[4*x+2] - ptr[4*x+1] + 0x100;
84 buffer[x][0] = (ptr[4*x+0] + 2*ptr[4*x+1] + ptr[4*x+2])>>2;
86 for(i=0;i<3;i++) {
87 int pred, diff;
89 PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
91 topleft[i]= top[i];
92 top[i]= buffer[x+1][i];
94 left[i]= buffer[x][i];
96 diff= ((left[i] - pred + 0x100)&0x1FF) - 0x100;
98 if(i==0)
99 ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
100 else
101 ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
105 }else{
106 int mb_x, mb_y, i;
107 const int mb_width = (width + s->mjpeg_hsample[0] - 1) / s->mjpeg_hsample[0];
108 const int mb_height = (height + s->mjpeg_vsample[0] - 1) / s->mjpeg_vsample[0];
110 for(mb_y = 0; mb_y < mb_height; mb_y++) {
111 if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < mb_width * 4 * 3 * s->mjpeg_hsample[0] * s->mjpeg_vsample[0]){
112 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
113 return -1;
115 for(mb_x = 0; mb_x < mb_width; mb_x++) {
116 if(mb_x==0 || mb_y==0){
117 for(i=0;i<3;i++) {
118 uint8_t *ptr;
119 int x, y, h, v, linesize;
120 h = s->mjpeg_hsample[i];
121 v = s->mjpeg_vsample[i];
122 linesize= p->linesize[i];
124 for(y=0; y<v; y++){
125 for(x=0; x<h; x++){
126 int pred;
128 ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
129 if(y==0 && mb_y==0){
130 if(x==0 && mb_x==0){
131 pred= 128;
132 }else{
133 pred= ptr[-1];
135 }else{
136 if(x==0 && mb_x==0){
137 pred= ptr[-linesize];
138 }else{
139 PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
143 if(i==0)
144 ff_mjpeg_encode_dc(s, (int8_t)(*ptr - pred), m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
145 else
146 ff_mjpeg_encode_dc(s, (int8_t)(*ptr - pred), m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
150 }else{
151 for(i=0;i<3;i++) {
152 uint8_t *ptr;
153 int x, y, h, v, linesize;
154 h = s->mjpeg_hsample[i];
155 v = s->mjpeg_vsample[i];
156 linesize= p->linesize[i];
158 for(y=0; y<v; y++){
159 for(x=0; x<h; x++){
160 int pred;
162 ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
163 //printf("%d %d %d %d %8X\n", mb_x, mb_y, x, y, ptr);
164 PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
166 if(i==0)
167 ff_mjpeg_encode_dc(s, (int8_t)(*ptr - pred), m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
168 else
169 ff_mjpeg_encode_dc(s, (int8_t)(*ptr - pred), m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
178 emms_c();
180 ff_mjpeg_encode_picture_trailer(s);
181 s->picture_number++;
183 flush_put_bits(&s->pb);
184 return pbBufPtr(&s->pb) - s->pb.buf;
185 // return (put_bits_count(&f->pb)+7)/8;
189 AVCodec ljpeg_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them
190 "ljpeg",
191 CODEC_TYPE_VIDEO,
192 CODEC_ID_LJPEG,
193 sizeof(MpegEncContext),
194 MPV_encode_init,
195 encode_picture_lossless,
196 MPV_encode_end,
197 .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),