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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 "internal.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 AVERROR_INVALIDDATA;
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  int ret;
118 
119  width = FFALIGN(width, 2);
120  height = FFALIGN(height, 2);
121  if (quality >= 0)
122  get_quant_quality(c, quality);
123  if (width != c->width || height != c->height) {
124  // also reserve space for a possible additional header
125  int buf_size = 24 + height * width * 3 / 2 + AV_LZO_OUTPUT_PADDING;
126  if (buf_size > INT_MAX/8)
127  return -1;
128  if ((ret = av_image_check_size(height, width, 0, avctx)) < 0)
129  return ret;
130  avctx->width = c->width = width;
131  avctx->height = c->height = height;
132  av_fast_malloc(&c->decomp_buf, &c->decomp_size,
133  buf_size);
134  if (!c->decomp_buf) {
135  av_log(avctx, AV_LOG_ERROR,
136  "Can't allocate decompression buffer.\n");
137  return AVERROR(ENOMEM);
138  }
139  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
140  c->lq, c->cq);
141  return 1;
142  } else if (quality != c->quality)
143  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,
144  c->lq, c->cq);
145 
146  return 0;
147 }
148 
149 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
150  AVPacket *avpkt)
151 {
152  const uint8_t *buf = avpkt->data;
153  int buf_size = avpkt->size;
154  NuvContext *c = avctx->priv_data;
155  AVFrame *picture = data;
156  int orig_size = buf_size;
157  int keyframe;
158  int size_change = 0;
159  int result, init_frame = !avctx->frame_number;
160  enum {
161  NUV_UNCOMPRESSED = '0',
162  NUV_RTJPEG = '1',
163  NUV_RTJPEG_IN_LZO = '2',
164  NUV_LZO = '3',
165  NUV_BLACK = 'N',
166  NUV_COPY_LAST = 'L'
167  } comptype;
168 
169  if (buf_size < 12) {
170  av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
171  return AVERROR_INVALIDDATA;
172  }
173 
174  // codec data (rtjpeg quant tables)
175  if (buf[0] == 'D' && buf[1] == 'R') {
176  int ret;
177  // skip rest of the frameheader.
178  buf = &buf[12];
179  buf_size -= 12;
180  ret = get_quant(avctx, c, buf, buf_size);
181  if (ret < 0)
182  return ret;
183  ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height, c->lq,
184  c->cq);
185  return orig_size;
186  }
187 
188  if (buf_size < 12 || buf[0] != 'V') {
189  av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");
190  return AVERROR_INVALIDDATA;
191  }
192  comptype = buf[1];
193  switch (comptype) {
194  case NUV_RTJPEG_IN_LZO:
195  case NUV_RTJPEG:
196  keyframe = !buf[2];
197  break;
198  case NUV_COPY_LAST:
199  keyframe = 0;
200  break;
201  default:
202  keyframe = 1;
203  break;
204  }
205 retry:
206  // skip rest of the frameheader.
207  buf = &buf[12];
208  buf_size -= 12;
209  if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {
210  int outlen = c->decomp_size - AV_LZO_OUTPUT_PADDING, inlen = buf_size;
211  if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen))
212  av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
213  buf = c->decomp_buf;
214  buf_size = c->decomp_size - AV_LZO_OUTPUT_PADDING - outlen;
215  }
216  if (c->codec_frameheader) {
217  int w, h, q;
218  if (buf_size < RTJPEG_HEADER_SIZE) {
219  av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");
220  return AVERROR_INVALIDDATA;
221  }
222  // There seem to exist two variants of this header: one starts with 'V'
223  // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,
224  // 1 byte header size (== 12), 1 byte version (== 0)
225  if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {
226  av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");
227  return AVERROR_INVALIDDATA;
228  }
229  w = AV_RL16(&buf[6]);
230  h = AV_RL16(&buf[8]);
231  q = buf[10];
232  if ((result = codec_reinit(avctx, w, h, q)) < 0)
233  return result;
234  if (result) {
235  buf = avpkt->data;
236  buf_size = avpkt->size;
237  size_change = 1;
238  goto retry;
239  }
240  buf = &buf[RTJPEG_HEADER_SIZE];
241  buf_size -= RTJPEG_HEADER_SIZE;
242  }
243 
244  if (size_change || keyframe) {
245  av_frame_unref(&c->pic);
246  init_frame = 1;
247  }
248 
249  if ((result = ff_reget_buffer(avctx, &c->pic)) < 0)
250  return result;
251  if (init_frame) {
252  memset(c->pic.data[0], 0, avctx->height * c->pic.linesize[0]);
253  memset(c->pic.data[1], 0x80, avctx->height * c->pic.linesize[1] / 2);
254  memset(c->pic.data[2], 0x80, avctx->height * c->pic.linesize[2] / 2);
255  }
256 
257  c->pic.pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
258  c->pic.key_frame = keyframe;
259  // decompress/copy/whatever data
260  switch (comptype) {
261  case NUV_LZO:
262  case NUV_UNCOMPRESSED: {
263  int height = c->height;
264  if (buf_size < c->width * height * 3 / 2) {
265  av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");
266  height = buf_size / c->width / 3 * 2;
267  }
268  if(height > 0)
269  copy_frame(&c->pic, buf, c->width, height);
270  break;
271  }
272  case NUV_RTJPEG_IN_LZO:
273  case NUV_RTJPEG:
274  ff_rtjpeg_decode_frame_yuv420(&c->rtj, &c->pic, buf, buf_size);
275  break;
276  case NUV_BLACK:
277  memset(c->pic.data[0], 0, c->width * c->height);
278  memset(c->pic.data[1], 128, c->width * c->height / 4);
279  memset(c->pic.data[2], 128, c->width * c->height / 4);
280  break;
281  case NUV_COPY_LAST:
282  /* nothing more to do here */
283  break;
284  default:
285  av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
286  return AVERROR_INVALIDDATA;
287  }
288 
289  if ((result = av_frame_ref(picture, &c->pic)) < 0)
290  return result;
291 
292  *got_frame = 1;
293  return orig_size;
294 }
295 
296 static av_cold int decode_init(AVCodecContext *avctx)
297 {
298  NuvContext *c = avctx->priv_data;
299  int ret;
300 
301  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
302  c->pic.data[0] = NULL;
303  c->decomp_buf = NULL;
304  c->quality = -1;
305  c->width = 0;
306  c->height = 0;
307 
308  c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');
309 
310  if (avctx->extradata_size)
311  get_quant(avctx, c, avctx->extradata, avctx->extradata_size);
312 
313  ff_dsputil_init(&c->dsp, avctx);
314 
315  if ((ret = codec_reinit(avctx, avctx->width, avctx->height, -1)) < 0)
316  return ret;
317 
318  return 0;
319 }
320 
321 static av_cold int decode_end(AVCodecContext *avctx)
322 {
323  NuvContext *c = avctx->priv_data;
324 
325  av_freep(&c->decomp_buf);
326  av_frame_unref(&c->pic);
327 
328  return 0;
329 }
330 
331 AVCodec ff_nuv_decoder = {
332  .name = "nuv",
333  .type = AVMEDIA_TYPE_VIDEO,
334  .id = AV_CODEC_ID_NUV,
335  .priv_data_size = sizeof(NuvContext),
336  .init = decode_init,
337  .close = decode_end,
338  .decode = decode_frame,
339  .capabilities = CODEC_CAP_DR1,
340  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),
341 };
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