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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/intreadwrite.h"
29 #include "libavutil/lzo.h"
30 #include "libavutil/imgutils.h"
31 #include "avcodec.h"
32 #include "idctdsp.h"
33 #include "internal.h"
34 #include "rtjpeg.h"
35 
36 typedef struct NuvContext {
37  AVFrame *pic;
38  int codec_frameheader;
39  int quality;
40  int width, height;
41  unsigned int decomp_size;
42  unsigned char *decomp_buf;
43  uint32_t lq[64], cq[64];
44  RTJpegContext rtj;
45 } NuvContext;
46 
47 static const uint8_t fallback_lquant[] = {
48  16, 11, 10, 16, 24, 40, 51, 61,
49  12, 12, 14, 19, 26, 58, 60, 55,
50  14, 13, 16, 24, 40, 57, 69, 56,
51  14, 17, 22, 29, 51, 87, 80, 62,
52  18, 22, 37, 56, 68, 109, 103, 77,
53  24, 35, 55, 64, 81, 104, 113, 92,
54  49, 64, 78, 87, 103, 121, 120, 101,
55  72, 92, 95, 98, 112, 100, 103, 99
56 };
57 
58 static const uint8_t fallback_cquant[] = {
59  17, 18, 24, 47, 99, 99, 99, 99,
60  18, 21, 26, 66, 99, 99, 99, 99,
61  24, 26, 56, 99, 99, 99, 99, 99,
62  47, 66, 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  99, 99, 99, 99, 99, 99, 99, 99
67 };
68 
69 /**
70  * @brief copy frame data from buffer to AVFrame, handling stride.
71  * @param f destination AVFrame
72  * @param src source buffer, does not use any line-stride
73  * @param width width of the video frame
74  * @param height height of the video frame
75  */
76 static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)
77 {
78  AVPicture pic;
79  avpicture_fill(&pic, src, AV_PIX_FMT_YUV420P, width, height);
80  av_picture_copy((AVPicture *)f, &pic, AV_PIX_FMT_YUV420P, width, height);
81 }
82 
83 /**
84  * @brief extract quantization tables from codec data into our context
85  */
86 static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf,
87  int size)
88 {
89  int i;
90  if (size < 2 * 64 * 4) {
91  av_log(avctx, AV_LOG_ERROR, "insufficient rtjpeg quant data\n");
92  return AVERROR_INVALIDDATA;
93  }
94  for (i = 0; i < 64; i++, buf += 4)
95  c->lq[i] = AV_RL32(buf);
96  for (i = 0; i < 64; i++, buf += 4)
97  c->cq[i] = AV_RL32(buf);
98  return 0;
99 }
100 
101 /**
102  * @brief set quantization tables from a quality value
103  */
104 static void get_quant_quality(NuvContext *c, int quality)
105 {
106  int i;
107  quality = FFMAX(quality, 1);
108  for (i = 0; i < 64; i++) {
109  c->lq[i] = (fallback_lquant[i] << 7) / quality;
110  c->cq[i] = (fallback_cquant[i] << 7) / quality;
111  }
112 }
113 
114 static int codec_reinit(AVCodecContext *avctx, int width, int height,
115  int quality)
116 {
117  NuvContext *c = avctx->priv_data;
118  int ret;
119 
120  width = FFALIGN(width, 2);
121  height = FFALIGN(height, 2);
122  if (quality >= 0)
123  get_quant_quality(c, quality);
124  if (width != c->width || height != c->height) {
125  // also reserve space for a possible additional header
126  int buf_size = height * width * 3 / 2
127  + FFMAX(AV_LZO_OUTPUT_PADDING, FF_INPUT_BUFFER_PADDING_SIZE)
128  + RTJPEG_HEADER_SIZE;
129  if (buf_size > INT_MAX/8)
130  return -1;
131  if ((ret = av_image_check_size(height, width, 0, avctx)) < 0)
132  return ret;
133  avctx->width = c->width = width;
134  avctx->height = c->height = height;
135  av_fast_malloc(&c->decomp_buf, &c->decomp_size,
136  buf_size);
137  if (!c->decomp_buf) {
138  av_log(avctx, AV_LOG_ERROR,
139  "Can't allocate decompression buffer.\n");
140  return AVERROR(ENOMEM);
141  }
142  ff_rtjpeg_decode_init(&c->rtj, c->width, c->height, c->lq, c->cq);
143  av_frame_unref(c->pic);
144  return 1;
145  } else if (quality != c->quality)
146  ff_rtjpeg_decode_init(&c->rtj, c->width, c->height, c->lq, c->cq);
147 
148  return 0;
149 }
150 
151 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
152  AVPacket *avpkt)
153 {
154  const uint8_t *buf = avpkt->data;
155  int buf_size = avpkt->size;
156  NuvContext *c = avctx->priv_data;
157  AVFrame *picture = data;
158  int orig_size = buf_size;
159  int keyframe, ret;
160  int size_change = 0;
161  int result, init_frame = !avctx->frame_number;
162  enum {
163  NUV_UNCOMPRESSED = '0',
164  NUV_RTJPEG = '1',
165  NUV_RTJPEG_IN_LZO = '2',
166  NUV_LZO = '3',
167  NUV_BLACK = 'N',
168  NUV_COPY_LAST = 'L'
169  } comptype;
170 
171  if (buf_size < 12) {
172  av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");
173  return AVERROR_INVALIDDATA;
174  }
175 
176  // codec data (rtjpeg quant tables)
177  if (buf[0] == 'D' && buf[1] == 'R') {
178  int ret;
179  // skip rest of the frameheader.
180  buf = &buf[12];
181  buf_size -= 12;
182  ret = get_quant(avctx, c, buf, buf_size);
183  if (ret < 0)
184  return ret;
185  ff_rtjpeg_decode_init(&c->rtj, c->width, c->height, c->lq, c->cq);
186  return orig_size;
187  }
188 
189  if (buf_size < 12 || buf[0] != 'V') {
190  av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");
191  return AVERROR_INVALIDDATA;
192  }
193  comptype = buf[1];
194  switch (comptype) {
195  case NUV_RTJPEG_IN_LZO:
196  case NUV_RTJPEG:
197  keyframe = !buf[2];
198  break;
199  case NUV_COPY_LAST:
200  keyframe = 0;
201  break;
202  default:
203  keyframe = 1;
204  break;
205  }
206 retry:
207  // skip rest of the frameheader.
208  buf = &buf[12];
209  buf_size -= 12;
210  if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {
211  int outlen = c->decomp_size - FFMAX(FF_INPUT_BUFFER_PADDING_SIZE, AV_LZO_OUTPUT_PADDING);
212  int inlen = buf_size;
213  if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen)) {
214  av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");
215  return AVERROR_INVALIDDATA;
216  }
217  buf = c->decomp_buf;
218  buf_size = c->decomp_size - FFMAX(FF_INPUT_BUFFER_PADDING_SIZE, AV_LZO_OUTPUT_PADDING) - outlen;
219  memset(c->decomp_buf + buf_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
220  }
221  if (c->codec_frameheader) {
222  int w, h, q;
223  if (buf_size < RTJPEG_HEADER_SIZE) {
224  av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");
225  return AVERROR_INVALIDDATA;
226  }
227  // There seem to exist two variants of this header: one starts with 'V'
228  // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,
229  // 1 byte header size (== 12), 1 byte version (== 0)
230  if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {
231  av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");
232  return AVERROR_INVALIDDATA;
233  }
234  w = AV_RL16(&buf[6]);
235  h = AV_RL16(&buf[8]);
236  q = buf[10];
237  if ((result = codec_reinit(avctx, w, h, q)) < 0)
238  return result;
239  if (result) {
240  buf = avpkt->data;
241  buf_size = avpkt->size;
242  size_change = 1;
243  goto retry;
244  }
245  buf = &buf[RTJPEG_HEADER_SIZE];
246  buf_size -= RTJPEG_HEADER_SIZE;
247  }
248 
249  if (size_change || keyframe) {
250  av_frame_unref(c->pic);
251  init_frame = 1;
252  }
253 
254  if ((result = ff_reget_buffer(avctx, c->pic)) < 0)
255  return result;
256  if (init_frame) {
257  memset(c->pic->data[0], 0, avctx->height * c->pic->linesize[0]);
258  memset(c->pic->data[1], 0x80, avctx->height * c->pic->linesize[1] / 2);
259  memset(c->pic->data[2], 0x80, avctx->height * c->pic->linesize[2] / 2);
260  }
261 
262  c->pic->pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
263  c->pic->key_frame = keyframe;
264  // decompress/copy/whatever data
265  switch (comptype) {
266  case NUV_LZO:
267  case NUV_UNCOMPRESSED: {
268  int height = c->height;
269  if (buf_size < c->width * height * 3 / 2) {
270  av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");
271  height = buf_size / c->width / 3 * 2;
272  }
273  if(height > 0)
274  copy_frame(c->pic, buf, c->width, height);
275  break;
276  }
277  case NUV_RTJPEG_IN_LZO:
278  case NUV_RTJPEG:
279  ret = ff_rtjpeg_decode_frame_yuv420(&c->rtj, c->pic, buf, buf_size);
280  if (ret < 0)
281  return ret;
282  break;
283  case NUV_BLACK:
284  memset(c->pic->data[0], 0, c->width * c->height);
285  memset(c->pic->data[1], 128, c->width * c->height / 4);
286  memset(c->pic->data[2], 128, c->width * c->height / 4);
287  break;
288  case NUV_COPY_LAST:
289  /* nothing more to do here */
290  break;
291  default:
292  av_log(avctx, AV_LOG_ERROR, "unknown compression\n");
293  return AVERROR_INVALIDDATA;
294  }
295 
296  if ((result = av_frame_ref(picture, c->pic)) < 0)
297  return result;
298 
299  *got_frame = 1;
300  return orig_size;
301 }
302 
303 static av_cold int decode_init(AVCodecContext *avctx)
304 {
305  NuvContext *c = avctx->priv_data;
306  int ret;
307 
308  c->pic = av_frame_alloc();
309  if (!c->pic)
310  return AVERROR(ENOMEM);
311 
312  avctx->pix_fmt = AV_PIX_FMT_YUV420P;
313  c->decomp_buf = NULL;
314  c->quality = -1;
315  c->width = 0;
316  c->height = 0;
317 
318  c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');
319 
320  if (avctx->extradata_size)
321  get_quant(avctx, c, avctx->extradata, avctx->extradata_size);
322 
323  ff_rtjpeg_init(&c->rtj, avctx);
324 
325  if ((ret = codec_reinit(avctx, avctx->width, avctx->height, -1)) < 0)
326  return ret;
327 
328  return 0;
329 }
330 
331 static av_cold int decode_end(AVCodecContext *avctx)
332 {
333  NuvContext *c = avctx->priv_data;
334 
335  av_freep(&c->decomp_buf);
336  av_frame_free(&c->pic);
337 
338  return 0;
339 }
340 
341 AVCodec ff_nuv_decoder = {
342  .name = "nuv",
343  .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),
344  .type = AVMEDIA_TYPE_VIDEO,
345  .id = AV_CODEC_ID_NUV,
346  .priv_data_size = sizeof(NuvContext),
347  .init = decode_init,
348  .close = decode_end,
349  .decode = decode_frame,
350  .capabilities = CODEC_CAP_DR1,
351 };
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