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nuv.c
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1 /*
2  * NuppelVideo decoder
3  * Copyright (c) 2006 Reimar Doeffinger
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <limits.h>
25 
26 #include "libavutil/bswap.h"
27 #include "libavutil/common.h"
28 #include "libavutil/lzo.h"
29 #include "libavutil/imgutils.h"
30 #include "avcodec.h"
31 #include "rtjpeg.h"
32 
33 typedef struct {
34  AVFrame pic;
35  int codec_frameheader;
36  int quality;
37  int width, height;
38  unsigned int decomp_size;
39  unsigned char *decomp_buf;
40  uint32_t lq[64], cq[64];
41  RTJpegContext rtj;
42  DSPContext dsp;
43 } NuvContext;
44 
45 static const uint8_t fallback_lquant[] = {
46  16, 11, 10, 16, 24, 40, 51, 61,
47  12, 12, 14, 19, 26, 58, 60, 55,
48  14, 13, 16, 24, 40, 57, 69, 56,
49  14, 17, 22, 29, 51, 87, 80, 62,
50  18, 22, 37, 56, 68, 109, 103, 77,
51  24, 35, 55, 64, 81, 104, 113, 92,
52  49, 64, 78, 87, 103, 121, 120, 101,
53  72, 92, 95, 98, 112, 100, 103, 99
54 };
55 
56 static const uint8_t fallback_cquant[] = {
57  17, 18, 24, 47, 99, 99, 99, 99,
58  18, 21, 26, 66, 99, 99, 99, 99,
59  24, 26, 56, 99, 99, 99, 99, 99,
60  47, 66, 99, 99, 99, 99, 99, 99,
61  99, 99, 99, 99, 99, 99, 99, 99,
62  99, 99, 99, 99, 99, 99, 99, 99,
63  99, 99, 99, 99, 99, 99, 99, 99,
64  99, 99, 99, 99, 99, 99, 99, 99
65 };
66 
67 /**
68  * @brief copy frame data from buffer to AVFrame, handling stride.
69  * @param f destination AVFrame
70  * @param src source buffer, does not use any line-stride
71  * @param width width of the video frame
72  * @param height height of the video frame
73  */
74 static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
75 {
76  AVPicture pic;
77  avpicture_fill(&pic, src, AV_PIX_FMT_YUV420P, width, height);
78  av_picture_copy((AVPicture *)f, &pic, AV_PIX_FMT_YUV420P, width, height);
79 }
80 
81 /**
82  * @brief extract quantization tables from codec data into our context
83  */
84 static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf,
85  int size)
86 {
87  int i;
88  if (size < 2 * 64 * 4) {
89  av_log(avctx, AV_LOG_ERROR, "insufficient rtjpeg quant data\n");
90  return AVERROR_INVALIDDATA;
91  }
92  for (i = 0; i < 64; i++, buf += 4)
93  c->lq[i] = AV_RL32(buf);
94  for (i = 0; i < 64; i++, buf += 4)
95  c->cq[i] = AV_RL32(buf);
96  return 0;
97 }
98 
99 /**
100  * @brief set quantization tables from a quality value
101  */
102 static void get_quant_quality(NuvContext *c, int quality)
103 {
104  int i;
105  quality = FFMAX(quality, 1);
106  for (i = 0; i < 64; i++) {
107  c->lq[i] = (fallback_lquant[i] << 7) / quality;
108  c->cq[i] = (fallback_cquant[i] << 7) / quality;
109  }
110 }
111 
112 static int codec_reinit(AVCodecContext *avctx, int width, int height,
113  int quality)
114 {
115  NuvContext *c = avctx->priv_data;
116  int ret;
117 
118  width = FFALIGN(width, 2);
119  height = FFALIGN(height, 2);
120  if (quality >= 0)
121  get_quant_quality(c, quality);
122  if (width != c->width || height != c->height) {
123  // also reserve space for a possible additional header
124  int buf_size = 24 + height * width * 3 / 2 + AV_LZO_OUTPUT_PADDING;
125  if (buf_size > INT_MAX/8)
126  return -1;
127  if ((ret = av_image_check_size(height, width, 0, avctx)) < 0)
128  return ret;
129  avctx->width = c->width = width;
130  avctx->height = c->height = height;
131  av_fast_malloc(&c->decomp_buf, &c->decomp_size,
132  buf_size);
133  if (!c->decomp_buf) {
134  av_log(avctx, AV_LOG_ERROR,
135  "Can't allocate decompression buffer.\n");
136  return AVERROR(ENOMEM);
137  }
138  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
139  c->lq, c->cq);
140  return 1;
141  } else if (quality != c->quality)
142  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
143  c->lq, c->cq);
144 
145  return 0;
146 }
147 
148 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
149  AVPacket *avpkt)
150 {
151  const uint8_t *buf = avpkt->data;
152  int buf_size = avpkt->size;
153  NuvContext *c = avctx->priv_data;
154  AVFrame *picture = data;
155  int orig_size = buf_size;
156  int keyframe;
157  int size_change = 0;
158  int result, init_frame = !avctx->frame_number;
159  enum {
160  NUV_UNCOMPRESSED = '0',
161  NUV_RTJPEG = '1',
162  NUV_RTJPEG_IN_LZO = '2',
163  NUV_LZO = '3',
164  NUV_BLACK = 'N',
165  NUV_COPY_LAST = 'L'
166  } comptype;
167 
168  if (buf_size < 12) {
169  av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
170  return AVERROR_INVALIDDATA;
171  }
172 
173  // codec data (rtjpeg quant tables)
174  if (buf[0] == 'D' && buf[1] == 'R') {
175  int ret;
176  // skip rest of the frameheader.
177  buf = &buf[12];
178  buf_size -= 12;
179  ret = get_quant(avctx, c, buf, buf_size);
180  if (ret < 0)
181  return ret;
182  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height, c->lq,
183  c->cq);
184  return orig_size;
185  }
186 
187  if (buf_size < 12 || buf[0] != 'V') {
188  av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");
189  return AVERROR_INVALIDDATA;
190  }
191  comptype = buf[1];
192  switch (comptype) {
193  case NUV_RTJPEG_IN_LZO:
194  case NUV_RTJPEG:
195  keyframe = !buf[2];
196  break;
197  case NUV_COPY_LAST:
198  keyframe = 0;
199  break;
200  default:
201  keyframe = 1;
202  break;
203  }
204 retry:
205  // skip rest of the frameheader.
206  buf = &buf[12];
207  buf_size -= 12;
208  if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {
209  int outlen = c->decomp_size - AV_LZO_OUTPUT_PADDING, inlen = buf_size;
210  if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen))
211  av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
212  buf = c->decomp_buf;
213  buf_size = c->decomp_size - AV_LZO_OUTPUT_PADDING - outlen;
214  }
215  if (c->codec_frameheader) {
216  int w, h, q;
217  if (buf_size < RTJPEG_HEADER_SIZE) {
218  av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");
219  return AVERROR_INVALIDDATA;
220  }
221  // There seem to exist two variants of this header: one starts with 'V'
222  // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,
223  // 1 byte header size (== 12), 1 byte version (== 0)
224  if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {
225  av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");
226  return AVERROR_INVALIDDATA;
227  }
228  w = AV_RL16(&buf[6]);
229  h = AV_RL16(&buf[8]);
230  q = buf[10];
231  if ((result = codec_reinit(avctx, w, h, q)) < 0)
232  return result;
233  if (result) {
234  buf = avpkt->data;
235  buf_size = avpkt->size;
236  size_change = 1;
237  goto retry;
238  }
239  buf = &buf[RTJPEG_HEADER_SIZE];
240  buf_size -= RTJPEG_HEADER_SIZE;
241  }
242 
243  if ((size_change || keyframe) && c->pic.data[0]) {
244  avctx->release_buffer(avctx, &c->pic);
245  init_frame = 1;
246  }
247  c->pic.reference = 3;
248  c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE |
249  FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
250  result = avctx->reget_buffer(avctx, &c->pic);
251  if (result < 0) {
252  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
253  return result;
254  }
255  if (init_frame) {
256  memset(c->pic.data[0], 0, avctx->height * c->pic.linesize[0]);
257  memset(c->pic.data[1], 0x80, avctx->height * c->pic.linesize[1] / 2);
258  memset(c->pic.data[2], 0x80, avctx->height * c->pic.linesize[2] / 2);
259  }
260 
261  c->pic.pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
262  c->pic.key_frame = keyframe;
263  // decompress/copy/whatever data
264  switch (comptype) {
265  case NUV_LZO:
266  case NUV_UNCOMPRESSED: {
267  int height = c->height;
268  if (buf_size < c->width * height * 3 / 2) {
269  av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");
270  height = buf_size / c->width / 3 * 2;
271  }
272  if(height > 0)
273  copy_frame(&c->pic, buf, c->width, height);
274  break;
275  }
276  case NUV_RTJPEG_IN_LZO:
277  case NUV_RTJPEG:
278  ff_rtjpeg_decode_frame_yuv420(&c->rtj, &c->pic, buf, buf_size);
279  break;
280  case NUV_BLACK:
281  memset(c->pic.data[0], 0, c->width * c->height);
282  memset(c->pic.data[1], 128, c->width * c->height / 4);
283  memset(c->pic.data[2], 128, c->width * c->height / 4);
284  break;
285  case NUV_COPY_LAST:
286  /* nothing more to do here */
287  break;
288  default:
289  av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
290  return AVERROR_INVALIDDATA;
291  }
292 
293  *picture = c->pic;
294  *got_frame = 1;
295  return orig_size;
296 }
297 
298 static av_cold int decode_init(AVCodecContext *avctx)
299 {
300  NuvContext *c = avctx->priv_data;
301  int ret;
302 
303  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
304  c->pic.data[0] = NULL;
305  c->decomp_buf = NULL;
306  c->quality = -1;
307  c->width = 0;
308  c->height = 0;
309 
310  c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');
311 
312  if (avctx->extradata_size)
313  get_quant(avctx, c, avctx->extradata, avctx->extradata_size);
314 
315  ff_dsputil_init(&c->dsp, avctx);
316 
317  if ((ret = codec_reinit(avctx, avctx->width, avctx->height, -1)) < 0)
318  return ret;
319 
320  return 0;
321 }
322 
323 static av_cold int decode_end(AVCodecContext *avctx)
324 {
325  NuvContext *c = avctx->priv_data;
326 
327  av_freep(&c->decomp_buf);
328  if (c->pic.data[0])
329  avctx->release_buffer(avctx, &c->pic);
330 
331  return 0;
332 }
333 
334 AVCodec ff_nuv_decoder = {
335  .name = "nuv",
336  .type = AVMEDIA_TYPE_VIDEO,
337  .id = AV_CODEC_ID_NUV,
338  .priv_data_size = sizeof(NuvContext),
339  .init = decode_init,
340  .close = decode_end,
341  .decode = decode_frame,
342  .capabilities = CODEC_CAP_DR1,
343  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),
344 };
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