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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 "avcodec.h"
34 #include "internal.h"
35 #include "mpegvideo.h"
36 #include "mjpeg.h"
37 #include "mjpegenc.h"
38 
39 
40 static int encode_picture_lossless(AVCodecContext *avctx, AVPacket *pkt,
41  const AVFrame *pict, int *got_packet)
42 {
43  MpegEncContext * const s = avctx->priv_data;
44  MJpegContext * const m = s->mjpeg_ctx;
45  const int width= s->width;
46  const int height= s->height;
47  AVFrame * const p = &s->current_picture.f;
48  const int predictor= avctx->prediction_method+1;
49  const int mb_width = (width + s->mjpeg_hsample[0] - 1) / s->mjpeg_hsample[0];
50  const int mb_height = (height + s->mjpeg_vsample[0] - 1) / s->mjpeg_vsample[0];
51  int ret, max_pkt_size = FF_MIN_BUFFER_SIZE;
52 
53  if (avctx->pix_fmt == AV_PIX_FMT_BGRA)
54  max_pkt_size += width * height * 3 * 4;
55  else {
56  max_pkt_size += mb_width * mb_height * 3 * 4
57  * s->mjpeg_hsample[0] * s->mjpeg_vsample[0];
58  }
59 
60  if (!s->edge_emu_buffer &&
61  (ret = ff_mpv_frame_size_alloc(s, pict->linesize[0])) < 0) {
62  av_log(avctx, AV_LOG_ERROR, "failed to allocate context scratch buffers.\n");
63  return ret;
64  }
65 
66  if ((ret = ff_alloc_packet2(avctx, pkt, max_pkt_size)) < 0)
67  return ret;
68 
69  init_put_bits(&s->pb, pkt->data, pkt->size);
70 
71  av_frame_unref(p);
72  ret = av_frame_ref(p, pict);
73  if (ret < 0)
74  return ret;
75  p->pict_type= AV_PICTURE_TYPE_I;
76  p->key_frame= 1;
77 
78  ff_mjpeg_encode_picture_header(s);
79 
80  s->header_bits= put_bits_count(&s->pb);
81 
82  if(avctx->pix_fmt == AV_PIX_FMT_BGR0
83  || avctx->pix_fmt == AV_PIX_FMT_BGRA
84  || avctx->pix_fmt == AV_PIX_FMT_BGR24){
85  int x, y, i;
86  const int linesize= p->linesize[0];
87  uint16_t (*buffer)[4]= (void *) s->rd_scratchpad;
88  int left[3], top[3], topleft[3];
89 
90  for(i=0; i<3; i++){
91  buffer[0][i]= 1 << (9 - 1);
92  }
93 
94  for(y = 0; y < height; y++) {
95  const int modified_predictor= y ? predictor : 1;
96  uint8_t *ptr = p->data[0] + (linesize * y);
97 
98  if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < width*3*4){
99  av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
100  return -1;
101  }
102 
103  for(i=0; i<3; i++){
104  top[i]= left[i]= topleft[i]= buffer[0][i];
105  }
106  for(x = 0; x < width; x++) {
107  if(avctx->pix_fmt == AV_PIX_FMT_BGR24){
108  buffer[x][1] = ptr[3*x+0] - ptr[3*x+1] + 0x100;
109  buffer[x][2] = ptr[3*x+2] - ptr[3*x+1] + 0x100;
110  buffer[x][0] = (ptr[3*x+0] + 2*ptr[3*x+1] + ptr[3*x+2])>>2;
111  }else{
112  buffer[x][1] = ptr[4*x+0] - ptr[4*x+1] + 0x100;
113  buffer[x][2] = ptr[4*x+2] - ptr[4*x+1] + 0x100;
114  buffer[x][0] = (ptr[4*x+0] + 2*ptr[4*x+1] + ptr[4*x+2])>>2;
115  }
116 
117  for(i=0;i<3;i++) {
118  int pred, diff;
119 
120  PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
121 
122  topleft[i]= top[i];
123  top[i]= buffer[x+1][i];
124 
125  left[i]= buffer[x][i];
126 
127  diff= ((left[i] - pred + 0x100)&0x1FF) - 0x100;
128 
129  if(i==0)
130  ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
131  else
132  ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
133  }
134  }
135  }
136  }else{
137  int mb_x, mb_y, i;
138 
139  for(mb_y = 0; mb_y < mb_height; mb_y++) {
140  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]){
141  av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");
142  return -1;
143  }
144  for(mb_x = 0; mb_x < mb_width; mb_x++) {
145  if(mb_x==0 || mb_y==0){
146  for(i=0;i<3;i++) {
147  uint8_t *ptr;
148  int x, y, h, v, linesize;
149  h = s->mjpeg_hsample[i];
150  v = s->mjpeg_vsample[i];
151  linesize= p->linesize[i];
152 
153  for(y=0; y<v; y++){
154  for(x=0; x<h; x++){
155  int pred;
156 
157  ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
158  if(y==0 && mb_y==0){
159  if(x==0 && mb_x==0){
160  pred= 128;
161  }else{
162  pred= ptr[-1];
163  }
164  }else{
165  if(x==0 && mb_x==0){
166  pred= ptr[-linesize];
167  }else{
168  PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
169  }
170  }
171 
172  if(i==0)
173  ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
174  else
175  ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
176  }
177  }
178  }
179  }else{
180  for(i=0;i<3;i++) {
181  uint8_t *ptr;
182  int x, y, h, v, linesize;
183  h = s->mjpeg_hsample[i];
184  v = s->mjpeg_vsample[i];
185  linesize= p->linesize[i];
186 
187  for(y=0; y<v; y++){
188  for(x=0; x<h; x++){
189  int pred;
190 
191  ptr = p->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
192  PREDICT(pred, ptr[-linesize-1], ptr[-linesize], ptr[-1], predictor);
193 
194  if(i==0)
195  ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly
196  else
197  ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);
198  }
199  }
200  }
201  }
202  }
203  }
204  }
205 
206  emms_c();
207  av_assert0(s->esc_pos == s->header_bits >> 3);
208  ff_mjpeg_encode_stuffing(s);
209  ff_mjpeg_encode_picture_trailer(s);
210  s->picture_number++;
211 
212  flush_put_bits(&s->pb);
213  pkt->size = put_bits_ptr(&s->pb) - s->pb.buf;
214  pkt->flags |= AV_PKT_FLAG_KEY;
215  *got_packet = 1;
216 
217  return 0;
218 // return (put_bits_count(&f->pb)+7)/8;
219 }
220 
221 
222 AVCodec ff_ljpeg_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them
223  .name = "ljpeg",
224  .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),
225  .type = AVMEDIA_TYPE_VIDEO,
226  .id = AV_CODEC_ID_LJPEG,
227  .priv_data_size = sizeof(MpegEncContext),
228  .init = ff_MPV_encode_init,
229  .encode2 = encode_picture_lossless,
230  .close = ff_MPV_encode_end,
231  .pix_fmts = (const enum AVPixelFormat[]){
232  AV_PIX_FMT_BGR24, AV_PIX_FMT_BGRA, AV_PIX_FMT_BGR0,
233  AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,
234  AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P,
235  AV_PIX_FMT_NONE},
236 };
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