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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 "libavutil/frame.h"
34 #include "libavutil/mem.h"
35 #include "libavutil/pixdesc.h"
36 
37 #include "avcodec.h"
38 #include "idctdsp.h"
39 #include "internal.h"
40 #include "mjpegenc_common.h"
41 #include "mpegvideo.h"
42 #include "mjpeg.h"
43 #include "mjpegenc.h"
44 
45 typedef struct LJpegEncContext {
48  uint16_t matrix[64];
49 
50  int vsample[3];
51  int hsample[3];
52 
53  uint16_t huff_code_dc_luminance[12];
57 
58  uint16_t (*scratch)[4];
60 
62  const AVFrame *frame)
63 {
64  LJpegEncContext *s = avctx->priv_data;
65  const int width = frame->width;
66  const int height = frame->height;
67  const int linesize = frame->linesize[0];
68  uint16_t (*buffer)[4] = s->scratch;
69  const int predictor = avctx->prediction_method+1;
70  int left[3], top[3], topleft[3];
71  int x, y, i;
72 
73  for (i = 0; i < 3; i++)
74  buffer[0][i] = 1 << (9 - 1);
75 
76  for (y = 0; y < height; y++) {
77  const int modified_predictor = y ? predictor : 1;
78  uint8_t *ptr = frame->data[0] + (linesize * y);
79 
80  if (pb->buf_end - pb->buf - (put_bits_count(pb) >> 3) < width * 3 * 4) {
81  av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");
82  return -1;
83  }
84 
85  for (i = 0; i < 3; i++)
86  top[i]= left[i]= topleft[i]= buffer[0][i];
87 
88  for (x = 0; x < width; x++) {
89  if(avctx->pix_fmt == AV_PIX_FMT_BGR24){
90  buffer[x][1] = ptr[3 * x + 0] - ptr[3 * x + 1] + 0x100;
91  buffer[x][2] = ptr[3 * x + 2] - ptr[3 * x + 1] + 0x100;
92  buffer[x][0] = (ptr[3 * x + 0] + 2 * ptr[3 * x + 1] + ptr[3 * x + 2]) >> 2;
93  }else{
94  buffer[x][1] = ptr[4 * x + 0] - ptr[4 * x + 1] + 0x100;
95  buffer[x][2] = ptr[4 * x + 2] - ptr[4 * x + 1] + 0x100;
96  buffer[x][0] = (ptr[4 * x + 0] + 2 * ptr[4 * x + 1] + ptr[4 * x + 2]) >> 2;
97  }
98 
99  for (i = 0; i < 3; i++) {
100  int pred, diff;
101 
102  PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);
103 
104  topleft[i] = top[i];
105  top[i] = buffer[x+1][i];
106 
107  left[i] = buffer[x][i];
108 
109  diff = ((left[i] - pred + 0x100) & 0x1FF) - 0x100;
110 
111  if (i == 0)
113  else
115  }
116  }
117  }
118 
119  return 0;
120 }
121 
123  const AVFrame *frame, int predictor,
124  int mb_x, int mb_y)
125 {
126  int i;
127 
128  if (mb_x == 0 || mb_y == 0) {
129  for (i = 0; i < 3; i++) {
130  uint8_t *ptr;
131  int x, y, h, v, linesize;
132  h = s->hsample[i];
133  v = s->vsample[i];
134  linesize = frame->linesize[i];
135 
136  for (y = 0; y < v; y++) {
137  for (x = 0; x < h; x++) {
138  int pred;
139 
140  ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
141  if (y == 0 && mb_y == 0) {
142  if (x == 0 && mb_x == 0)
143  pred = 128;
144  else
145  pred = ptr[-1];
146  } else {
147  if (x == 0 && mb_x == 0) {
148  pred = ptr[-linesize];
149  } else {
150  PREDICT(pred, ptr[-linesize - 1], ptr[-linesize],
151  ptr[-1], predictor);
152  }
153  }
154 
155  if (i == 0)
156  ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly
157  else
159  }
160  }
161  }
162  } else {
163  for (i = 0; i < 3; i++) {
164  uint8_t *ptr;
165  int x, y, h, v, linesize;
166  h = s->hsample[i];
167  v = s->vsample[i];
168  linesize = frame->linesize[i];
169 
170  for (y = 0; y < v; y++) {
171  for (x = 0; x < h; x++) {
172  int pred;
173 
174  ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap
175  PREDICT(pred, ptr[-linesize - 1], ptr[-linesize], ptr[-1], predictor);
176 
177  if (i == 0)
178  ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly
179  else
181  }
182  }
183  }
184  }
185 }
186 
188  const AVFrame *frame)
189 {
190  const int predictor = avctx->prediction_method + 1;
191  LJpegEncContext *s = avctx->priv_data;
192  const int mb_width = (avctx->width + s->hsample[0] - 1) / s->hsample[0];
193  const int mb_height = (avctx->height + s->vsample[0] - 1) / s->vsample[0];
194  int mb_x, mb_y;
195 
196  for (mb_y = 0; mb_y < mb_height; mb_y++) {
197  if (pb->buf_end - pb->buf - (put_bits_count(pb) >> 3) <
198  mb_width * 4 * 3 * s->hsample[0] * s->vsample[0]) {
199  av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");
200  return -1;
201  }
202 
203  for (mb_x = 0; mb_x < mb_width; mb_x++)
204  ljpeg_encode_yuv_mb(s, pb, frame, predictor, mb_x, mb_y);
205  }
206 
207  return 0;
208 }
209 
211  const AVFrame *pict, int *got_packet)
212 {
213  LJpegEncContext *s = avctx->priv_data;
214  PutBitContext pb;
215  const int width = avctx->width;
216  const int height = avctx->height;
217  const int mb_width = (width + s->hsample[0] - 1) / s->hsample[0];
218  const int mb_height = (height + s->vsample[0] - 1) / s->vsample[0];
219  int max_pkt_size = FF_MIN_BUFFER_SIZE;
220  int ret, header_bits;
221 
222  if( avctx->pix_fmt == AV_PIX_FMT_BGR0
223  || avctx->pix_fmt == AV_PIX_FMT_BGRA
224  || avctx->pix_fmt == AV_PIX_FMT_BGR24)
225  max_pkt_size += width * height * 3 * 4;
226  else {
227  max_pkt_size += mb_width * mb_height * 3 * 4
228  * s->hsample[0] * s->vsample[0];
229  }
230 
231  if ((ret = ff_alloc_packet2(avctx, pkt, max_pkt_size)) < 0)
232  return ret;
233 
234  init_put_bits(&pb, pkt->data, pkt->size);
235 
237  s->matrix, s->matrix);
238 
239  header_bits = put_bits_count(&pb);
240 
241  if( avctx->pix_fmt == AV_PIX_FMT_BGR0
242  || avctx->pix_fmt == AV_PIX_FMT_BGRA
243  || avctx->pix_fmt == AV_PIX_FMT_BGR24)
244  ret = ljpeg_encode_bgr(avctx, &pb, pict);
245  else
246  ret = ljpeg_encode_yuv(avctx, &pb, pict);
247  if (ret < 0)
248  return ret;
249 
250  emms_c();
251 
252  ff_mjpeg_escape_FF(&pb, header_bits >> 3);
253  ff_mjpeg_encode_picture_trailer(&pb, header_bits);
254 
255  flush_put_bits(&pb);
256  pkt->size = put_bits_ptr(&pb) - pb.buf;
257  pkt->flags |= AV_PKT_FLAG_KEY;
258  *got_packet = 1;
259 
260  return 0;
261 }
262 
264 {
265  LJpegEncContext *s = avctx->priv_data;
266 
267  av_frame_free(&avctx->coded_frame);
268  av_freep(&s->scratch);
269 
270  return 0;
271 }
272 
274 {
275  LJpegEncContext *s = avctx->priv_data;
276 
277  if ((avctx->pix_fmt == AV_PIX_FMT_YUV420P ||
278  avctx->pix_fmt == AV_PIX_FMT_YUV422P ||
279  avctx->pix_fmt == AV_PIX_FMT_YUV444P ||
280  avctx->color_range == AVCOL_RANGE_MPEG) &&
282  av_log(avctx, AV_LOG_ERROR,
283  "Limited range YUV is non-standard, set strict_std_compliance to "
284  "at least unofficial to use it.\n");
285  return AVERROR(EINVAL);
286  }
287 
288  avctx->coded_frame = av_frame_alloc();
289  if (!avctx->coded_frame)
290  return AVERROR(ENOMEM);
291 
293  avctx->coded_frame->key_frame = 1;
294 
295  s->scratch = av_malloc_array(avctx->width + 1, sizeof(*s->scratch));
296  if (!s->scratch)
297  goto fail;
298 
299  ff_idctdsp_init(&s->idsp, avctx);
302 
303  ff_mjpeg_init_hvsample(avctx, s->hsample, s->vsample);
304 
313 
314  return 0;
315 fail:
316  ljpeg_encode_close(avctx);
317  return AVERROR(ENOMEM);
318 }
319 
321  .name = "ljpeg",
322  .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),
323  .type = AVMEDIA_TYPE_VIDEO,
324  .id = AV_CODEC_ID_LJPEG,
325  .priv_data_size = sizeof(LJpegEncContext),
327  .encode2 = ljpeg_encode_frame,
330  .pix_fmts = (const enum AVPixelFormat[]){
335 };