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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 "dsputil.h"
32 #include "rtjpeg.h"
33 
34 typedef struct {
35  AVFrame pic;
36  int codec_frameheader;
37  int quality;
38  int width, height;
39  unsigned int decomp_size;
40  unsigned char *decomp_buf;
41  uint32_t lq[64], cq[64];
42  RTJpegContext rtj;
43  DSPContext dsp;
44 } NuvContext;
45 
46 static const uint8_t fallback_lquant[] = {
47  16, 11, 10, 16, 24, 40, 51, 61,
48  12, 12, 14, 19, 26, 58, 60, 55,
49  14, 13, 16, 24, 40, 57, 69, 56,
50  14, 17, 22, 29, 51, 87, 80, 62,
51  18, 22, 37, 56, 68, 109, 103, 77,
52  24, 35, 55, 64, 81, 104, 113, 92,
53  49, 64, 78, 87, 103, 121, 120, 101,
54  72, 92, 95, 98, 112, 100, 103, 99
55 };
56 
57 static const uint8_t fallback_cquant[] = {
58  17, 18, 24, 47, 99, 99, 99, 99,
59  18, 21, 26, 66, 99, 99, 99, 99,
60  24, 26, 56, 99, 99, 99, 99, 99,
61  47, 66, 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  99, 99, 99, 99, 99, 99, 99, 99
66 };
67 
68 /**
69  * @brief copy frame data from buffer to AVFrame, handling stride.
70  * @param f destination AVFrame
71  * @param src source buffer, does not use any line-stride
72  * @param width width of the video frame
73  * @param height height of the video frame
74  */
75 static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
76 {
77  AVPicture pic;
78  avpicture_fill(&pic, src, AV_PIX_FMT_YUV420P, width, height);
79  av_picture_copy((AVPicture *)f, &pic, AV_PIX_FMT_YUV420P, width, height);
80 }
81 
82 /**
83  * @brief extract quantization tables from codec data into our context
84  */
85 static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf,
86  int size)
87 {
88  int i;
89  if (size < 2 * 64 * 4) {
90  av_log(avctx, AV_LOG_ERROR, "insufficient rtjpeg quant data\n");
91  return -1;
92  }
93  for (i = 0; i < 64; i++, buf += 4)
94  c->lq[i] = AV_RL32(buf);
95  for (i = 0; i < 64; i++, buf += 4)
96  c->cq[i] = AV_RL32(buf);
97  return 0;
98 }
99 
100 /**
101  * @brief set quantization tables from a quality value
102  */
103 static void get_quant_quality(NuvContext *c, int quality)
104 {
105  int i;
106  quality = FFMAX(quality, 1);
107  for (i = 0; i < 64; i++) {
108  c->lq[i] = (fallback_lquant[i] << 7) / quality;
109  c->cq[i] = (fallback_cquant[i] << 7) / quality;
110  }
111 }
112 
113 static int codec_reinit(AVCodecContext *avctx, int width, int height,
114  int quality)
115 {
116  NuvContext *c = avctx->priv_data;
117  width = FFALIGN(width, 2);
118  height = FFALIGN(height, 2);
119  if (quality >= 0)
120  get_quant_quality(c, quality);
121  if (width != c->width || height != c->height) {
122  // also reserve space for a possible additional header
123  int buf_size = 24 + height * width * 3 / 2 + AV_LZO_OUTPUT_PADDING;
124  if (av_image_check_size(height, width, 0, avctx) < 0 ||
125  buf_size > INT_MAX/8)
126  return -1;
127  avctx->width = c->width = width;
128  avctx->height = c->height = height;
129  av_fast_malloc(&c->decomp_buf, &c->decomp_size,
130  buf_size);
131  if (!c->decomp_buf) {
132  av_log(avctx, AV_LOG_ERROR,
133  "Can't allocate decompression buffer.\n");
134  return AVERROR(ENOMEM);
135  }
136  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
137  c->lq, c->cq);
138  return 1;
139  } else if (quality != c->quality)
140  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
141  c->lq, c->cq);
142 
143  return 0;
144 }
145 
146 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
147  AVPacket *avpkt)
148 {
149  const uint8_t *buf = avpkt->data;
150  int buf_size = avpkt->size;
151  NuvContext *c = avctx->priv_data;
152  AVFrame *picture = data;
153  int orig_size = buf_size;
154  int keyframe;
155  int size_change = 0;
156  int result;
157  enum {
158  NUV_UNCOMPRESSED = '0',
159  NUV_RTJPEG = '1',
160  NUV_RTJPEG_IN_LZO = '2',
161  NUV_LZO = '3',
162  NUV_BLACK = 'N',
163  NUV_COPY_LAST = 'L'
164  } comptype;
165 
166  if (buf_size < 12) {
167  av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
168  return -1;
169  }
170 
171  // codec data (rtjpeg quant tables)
172  if (buf[0] == 'D' && buf[1] == 'R') {
173  int ret;
174  // skip rest of the frameheader.
175  buf = &buf[12];
176  buf_size -= 12;
177  ret = get_quant(avctx, c, buf, buf_size);
178  if (ret < 0)
179  return ret;
180  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height, c->lq,
181  c->cq);
182  return orig_size;
183  }
184 
185  if (buf_size < 12 || buf[0] != 'V') {
186  av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");
187  return -1;
188  }
189  comptype = buf[1];
190  switch (comptype) {
191  case NUV_RTJPEG_IN_LZO:
192  case NUV_RTJPEG:
193  keyframe = !buf[2];
194  break;
195  case NUV_COPY_LAST:
196  keyframe = 0;
197  break;
198  default:
199  keyframe = 1;
200  break;
201  }
202 retry:
203  // skip rest of the frameheader.
204  buf = &buf[12];
205  buf_size -= 12;
206  if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {
207  int outlen = c->decomp_size - AV_LZO_OUTPUT_PADDING, inlen = buf_size;
208  if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen))
209  av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
210  buf = c->decomp_buf;
211  buf_size = c->decomp_size - AV_LZO_OUTPUT_PADDING - outlen;
212  }
213  if (c->codec_frameheader) {
214  int w, h, q;
215  int res;
216  if (buf_size < RTJPEG_HEADER_SIZE) {
217  av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");
218  return AVERROR_INVALIDDATA;
219  }
220  // There seem to exist two variants of this header: one starts with 'V'
221  // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,
222  // 1 byte header size (== 12), 1 byte version (== 0)
223  if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {
224  av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");
225  return AVERROR_INVALIDDATA;
226  }
227  w = AV_RL16(&buf[6]);
228  h = AV_RL16(&buf[8]);
229  q = buf[10];
230  res = codec_reinit(avctx, w, h, q);
231  if (res < 0)
232  return res;
233  if (res) {
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  c->pic.reference = 3;
246  c->pic.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_READABLE |
247  FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
248  result = avctx->reget_buffer(avctx, &c->pic);
249  if (result < 0) {
250  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
251  return -1;
252  }
253 
254  c->pic.pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
255  c->pic.key_frame = keyframe;
256  // decompress/copy/whatever data
257  switch (comptype) {
258  case NUV_LZO:
259  case NUV_UNCOMPRESSED: {
260  int height = c->height;
261  if (buf_size < c->width * height * 3 / 2) {
262  av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");
263  height = buf_size / c->width / 3 * 2;
264  }
265  if(height > 0)
266  copy_frame(&c->pic, buf, c->width, height);
267  break;
268  }
269  case NUV_RTJPEG_IN_LZO:
270  case NUV_RTJPEG:
271  ff_rtjpeg_decode_frame_yuv420(&c->rtj, &c->pic, buf, buf_size);
272  break;
273  case NUV_BLACK:
274  memset(c->pic.data[0], 0, c->width * c->height);
275  memset(c->pic.data[1], 128, c->width * c->height / 4);
276  memset(c->pic.data[2], 128, c->width * c->height / 4);
277  break;
278  case NUV_COPY_LAST:
279  /* nothing more to do here */
280  break;
281  default:
282  av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
283  return -1;
284  }
285 
286  *picture = c->pic;
287  *got_frame = 1;
288  return orig_size;
289 }
290 
291 static av_cold int decode_init(AVCodecContext *avctx)
292 {
293  NuvContext *c = avctx->priv_data;
294  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
295  c->pic.data[0] = NULL;
296  c->decomp_buf = NULL;
297  c->quality = -1;
298  c->width = 0;
299  c->height = 0;
300 
301  c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');
302 
303  if (avctx->extradata_size)
304  get_quant(avctx, c, avctx->extradata, avctx->extradata_size);
305 
306  ff_dsputil_init(&c->dsp, avctx);
307 
308  if (codec_reinit(avctx, avctx->width, avctx->height, -1) < 0)
309  return 1;
310 
311  return 0;
312 }
313 
314 static av_cold int decode_end(AVCodecContext *avctx)
315 {
316  NuvContext *c = avctx->priv_data;
317 
318  av_freep(&c->decomp_buf);
319  if (c->pic.data[0])
320  avctx->release_buffer(avctx, &c->pic);
321 
322  return 0;
323 }
324 
325 AVCodec ff_nuv_decoder = {
326  .name = "nuv",
327  .type = AVMEDIA_TYPE_VIDEO,
328  .id = AV_CODEC_ID_NUV,
329  .priv_data_size = sizeof(NuvContext),
330  .init = decode_init,
331  .close = decode_end,
332  .decode = decode_frame,
333  .capabilities = CODEC_CAP_DR1,
334  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),
335 };
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