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rawdec.c
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1 /*
2  * Raw Video Decoder
3  * Copyright (c) 2001 Fabrice Bellard
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 /**
23  * @file
24  * Raw Video Decoder
25  */
26 
27 #include "avcodec.h"
28 #include "bswapdsp.h"
29 #include "get_bits.h"
30 #include "internal.h"
31 #include "raw.h"
32 #include "libavutil/avassert.h"
33 #include "libavutil/buffer.h"
34 #include "libavutil/common.h"
35 #include "libavutil/intreadwrite.h"
36 #include "libavutil/imgutils.h"
37 #include "libavutil/opt.h"
38 
39 typedef struct RawVideoContext {
40  AVClass *av_class;
41  AVBufferRef *palette;
42  int frame_size; /* size of the frame in bytes */
43  int flip;
44  int is_2_4_bpp; // 2 or 4 bpp raw in avi/mov
45  int is_yuv2;
46  int is_lt_16bpp; // 16bpp pixfmt and bits_per_coded_sample < 16
47  int tff;
48 
49  BswapDSPContext bbdsp;
50  void *bitstream_buf;
51  unsigned int bitstream_buf_size;
52 } RawVideoContext;
53 
54 static const AVOption options[]={
55 {"top", "top field first", offsetof(RawVideoContext, tff), AV_OPT_TYPE_INT, {.i64 = -1}, -1, 1, AV_OPT_FLAG_DECODING_PARAM|AV_OPT_FLAG_VIDEO_PARAM},
56 {NULL}
57 };
58 
59 static const AVClass rawdec_class = {
60  .class_name = "rawdec",
61  .option = options,
62  .version = LIBAVUTIL_VERSION_INT,
63 };
64 
65 #if LIBAVCODEC_VERSION_MAJOR < 55
66 enum AVPixelFormat ff_find_pix_fmt(const PixelFormatTag *tags, unsigned int fourcc)
67 {
68  return avpriv_find_pix_fmt(tags, fourcc);
69 }
70 #endif
71 
72 static av_cold int raw_init_decoder(AVCodecContext *avctx)
73 {
74  RawVideoContext *context = avctx->priv_data;
75  const AVPixFmtDescriptor *desc;
76 
77  ff_bswapdsp_init(&context->bbdsp);
78 
79  if ( avctx->codec_tag == MKTAG('r','a','w',' ')
80  || avctx->codec_tag == MKTAG('N','O','1','6'))
81  avctx->pix_fmt = avpriv_find_pix_fmt(avpriv_pix_fmt_bps_mov,
82  avctx->bits_per_coded_sample);
83  else if (avctx->codec_tag == MKTAG('W', 'R', 'A', 'W'))
84  avctx->pix_fmt = avpriv_find_pix_fmt(avpriv_pix_fmt_bps_avi,
85  avctx->bits_per_coded_sample);
86  else if (avctx->codec_tag && (avctx->codec_tag & 0xFFFFFF) != MKTAG('B','I','T', 0))
87  avctx->pix_fmt = avpriv_find_pix_fmt(ff_raw_pix_fmt_tags, avctx->codec_tag);
88  else if (avctx->pix_fmt == AV_PIX_FMT_NONE && avctx->bits_per_coded_sample)
89  avctx->pix_fmt = avpriv_find_pix_fmt(avpriv_pix_fmt_bps_avi,
90  avctx->bits_per_coded_sample);
91 
92  desc = av_pix_fmt_desc_get(avctx->pix_fmt);
93  if (!desc) {
94  av_log(avctx, AV_LOG_ERROR, "Invalid pixel format.\n");
95  return AVERROR(EINVAL);
96  }
97 
98  if (desc->flags & (AV_PIX_FMT_FLAG_PAL | AV_PIX_FMT_FLAG_PSEUDOPAL)) {
99  context->palette = av_buffer_alloc(AVPALETTE_SIZE);
100  if (!context->palette)
101  return AVERROR(ENOMEM);
102  if (desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)
103  avpriv_set_systematic_pal2((uint32_t*)context->palette->data, avctx->pix_fmt);
104  else
105  memset(context->palette->data, 0, AVPALETTE_SIZE);
106  }
107 
108  if ((avctx->bits_per_coded_sample == 4 || avctx->bits_per_coded_sample == 2) &&
109  avctx->pix_fmt == AV_PIX_FMT_PAL8 &&
110  (!avctx->codec_tag || avctx->codec_tag == MKTAG('r','a','w',' '))) {
111  context->is_2_4_bpp = 1;
112  context->frame_size = avpicture_get_size(avctx->pix_fmt,
113  FFALIGN(avctx->width, 16),
114  avctx->height);
115  } else {
116  context->is_lt_16bpp = av_get_bits_per_pixel(desc) == 16 && avctx->bits_per_coded_sample && avctx->bits_per_coded_sample < 16;
117  context->frame_size = avpicture_get_size(avctx->pix_fmt, avctx->width,
118  avctx->height);
119  }
120 
121  if ((avctx->extradata_size >= 9 &&
122  !memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9)) ||
123  avctx->codec_tag == MKTAG('c','y','u','v') ||
124  avctx->codec_tag == MKTAG(3, 0, 0, 0) ||
125  avctx->codec_tag == MKTAG('W','R','A','W'))
126  context->flip = 1;
127 
128  if (avctx->codec_tag == AV_RL32("yuv2") &&
129  avctx->pix_fmt == AV_PIX_FMT_YUYV422)
130  context->is_yuv2 = 1;
131 
132  return 0;
133 }
134 
135 static void flip(AVCodecContext *avctx, AVPicture *picture)
136 {
137  picture->data[0] += picture->linesize[0] * (avctx->height - 1);
138  picture->linesize[0] *= -1;
139 }
140 
141 /*
142  * Scale sample to 16-bit resolution
143  */
144 #define SCALE16(x, bits) (((x) << (16 - (bits))) | ((x) >> (2 * (bits) - 16)))
145 
146 /**
147  * Scale buffer to 16 bits per coded sample resolution
148  */
149 #define MKSCALE16(name, r16, w16) \
150 static void name(AVCodecContext *avctx, uint8_t * dst, const uint8_t *buf, int buf_size, int packed) \
151 { \
152  int i; \
153  if (!packed) { \
154  for (i = 0; i + 1 < buf_size; i += 2) \
155  w16(dst + i, SCALE16(r16(buf + i), avctx->bits_per_coded_sample)); \
156  } else { \
157  GetBitContext gb; \
158  init_get_bits(&gb, buf, buf_size * 8); \
159  for (i = 0; i < avctx->width * avctx->height; i++) { \
160  int sample = get_bits(&gb, avctx->bits_per_coded_sample); \
161  w16(dst + i*2, SCALE16(sample, avctx->bits_per_coded_sample)); \
162  } \
163  } \
164 }
165 
166 MKSCALE16(scale16be, AV_RB16, AV_WB16)
167 MKSCALE16(scale16le, AV_RL16, AV_WL16)
168 
169 static int raw_decode(AVCodecContext *avctx, void *data, int *got_frame,
170  AVPacket *avpkt)
171 {
172  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(avctx->pix_fmt);
173  RawVideoContext *context = avctx->priv_data;
174  const uint8_t *buf = avpkt->data;
175  int buf_size = avpkt->size;
176  int linesize_align = 4;
177  int res, len;
178  int need_copy = !avpkt->buf || context->is_2_4_bpp || context->is_yuv2 || context->is_lt_16bpp;
179 
180  AVFrame *frame = data;
181  AVPicture *picture = data;
182 
183  frame->pict_type = AV_PICTURE_TYPE_I;
184  frame->key_frame = 1;
185 
186  res = ff_decode_frame_props(avctx, frame);
187  if (res < 0)
188  return res;
189 
190  av_frame_set_pkt_pos (frame, avctx->internal->pkt->pos);
191  av_frame_set_pkt_duration(frame, avctx->internal->pkt->duration);
192 
193  if (context->tff >= 0) {
194  frame->interlaced_frame = 1;
195  frame->top_field_first = context->tff;
196  }
197 
198  if ((res = av_image_check_size(avctx->width, avctx->height, 0, avctx)) < 0)
199  return res;
200 
201  if (need_copy)
202  frame->buf[0] = av_buffer_alloc(FFMAX(context->frame_size, buf_size));
203  else
204  frame->buf[0] = av_buffer_ref(avpkt->buf);
205  if (!frame->buf[0])
206  return AVERROR(ENOMEM);
207 
208  //2bpp and 4bpp raw in avi and mov (yes this is ugly ...)
209  if (context->is_2_4_bpp) {
210  int i;
211  uint8_t *dst = frame->buf[0]->data;
212  buf_size = context->frame_size - AVPALETTE_SIZE;
213  if (avctx->bits_per_coded_sample == 4) {
214  for (i = 0; 2 * i + 1 < buf_size && i<avpkt->size; i++) {
215  dst[2 * i + 0] = buf[i] >> 4;
216  dst[2 * i + 1] = buf[i] & 15;
217  }
218  linesize_align = 8;
219  } else {
220  av_assert0(avctx->bits_per_coded_sample == 2);
221  for (i = 0; 4 * i + 3 < buf_size && i<avpkt->size; i++) {
222  dst[4 * i + 0] = buf[i] >> 6;
223  dst[4 * i + 1] = buf[i] >> 4 & 3;
224  dst[4 * i + 2] = buf[i] >> 2 & 3;
225  dst[4 * i + 3] = buf[i] & 3;
226  }
227  linesize_align = 16;
228  }
229  buf = dst;
230  } else if (context->is_lt_16bpp) {
231  uint8_t *dst = frame->buf[0]->data;
232  int packed = (avctx->codec_tag & 0xFFFFFF) == MKTAG('B','I','T', 0);
233  int swap = avctx->codec_tag >> 24;
234 
235  if (packed && swap) {
236  av_fast_padded_malloc(&context->bitstream_buf, &context->bitstream_buf_size, buf_size);
237  if (!context->bitstream_buf)
238  return AVERROR(ENOMEM);
239  if (swap == 16)
240  context->bbdsp.bswap16_buf(context->bitstream_buf, (const uint16_t*)buf, buf_size / 2);
241  else if (swap == 32)
242  context->bbdsp.bswap_buf(context->bitstream_buf, (const uint32_t*)buf, buf_size / 4);
243  else
244  return AVERROR_INVALIDDATA;
245  buf = context->bitstream_buf;
246  }
247 
248  if (desc->flags & AV_PIX_FMT_FLAG_BE)
249  scale16be(avctx, dst, buf, buf_size, packed);
250  else
251  scale16le(avctx, dst, buf, buf_size, packed);
252 
253  buf = dst;
254  } else if (need_copy) {
255  memcpy(frame->buf[0]->data, buf, buf_size);
256  buf = frame->buf[0]->data;
257  }
258 
259  if (avctx->codec_tag == MKTAG('A', 'V', '1', 'x') ||
260  avctx->codec_tag == MKTAG('A', 'V', 'u', 'p'))
261  buf += buf_size - context->frame_size;
262 
263  len = context->frame_size - (avctx->pix_fmt==AV_PIX_FMT_PAL8 ? AVPALETTE_SIZE : 0);
264  if (buf_size < len && (avctx->codec_tag & 0xFFFFFF) != MKTAG('B','I','T', 0)) {
265  av_log(avctx, AV_LOG_ERROR, "Invalid buffer size, packet size %d < expected frame_size %d\n", buf_size, len);
266  av_buffer_unref(&frame->buf[0]);
267  return AVERROR(EINVAL);
268  }
269 
270  if ((res = avpicture_fill(picture, buf, avctx->pix_fmt,
271  avctx->width, avctx->height)) < 0) {
272  av_buffer_unref(&frame->buf[0]);
273  return res;
274  }
275 
276  if (avctx->pix_fmt == AV_PIX_FMT_PAL8) {
277  const uint8_t *pal = av_packet_get_side_data(avpkt, AV_PKT_DATA_PALETTE,
278  NULL);
279 
280  if (pal) {
281  av_buffer_unref(&context->palette);
282  context->palette = av_buffer_alloc(AVPALETTE_SIZE);
283  if (!context->palette) {
284  av_buffer_unref(&frame->buf[0]);
285  return AVERROR(ENOMEM);
286  }
287  memcpy(context->palette->data, pal, AVPALETTE_SIZE);
288  frame->palette_has_changed = 1;
289  }
290  }
291 
292  if ((avctx->pix_fmt==AV_PIX_FMT_BGR24 ||
293  avctx->pix_fmt==AV_PIX_FMT_GRAY8 ||
294  avctx->pix_fmt==AV_PIX_FMT_RGB555LE ||
295  avctx->pix_fmt==AV_PIX_FMT_RGB555BE ||
296  avctx->pix_fmt==AV_PIX_FMT_RGB565LE ||
297  avctx->pix_fmt==AV_PIX_FMT_MONOWHITE ||
298  avctx->pix_fmt==AV_PIX_FMT_PAL8) &&
299  FFALIGN(frame->linesize[0], linesize_align) * avctx->height <= buf_size)
300  frame->linesize[0] = FFALIGN(frame->linesize[0], linesize_align);
301 
302  if (avctx->pix_fmt == AV_PIX_FMT_NV12 && avctx->codec_tag == MKTAG('N', 'V', '1', '2') &&
303  FFALIGN(frame->linesize[0], linesize_align) * avctx->height +
304  FFALIGN(frame->linesize[1], linesize_align) * ((avctx->height + 1) / 2) <= buf_size) {
305  int la0 = FFALIGN(frame->linesize[0], linesize_align);
306  frame->data[1] += (la0 - frame->linesize[0]) * avctx->height;
307  frame->linesize[0] = la0;
308  frame->linesize[1] = FFALIGN(frame->linesize[1], linesize_align);
309  }
310 
311  if ((avctx->pix_fmt == AV_PIX_FMT_PAL8 && buf_size < context->frame_size) ||
312  (desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)) {
313  frame->buf[1] = av_buffer_ref(context->palette);
314  if (!frame->buf[1]) {
315  av_buffer_unref(&frame->buf[0]);
316  return AVERROR(ENOMEM);
317  }
318  frame->data[1] = frame->buf[1]->data;
319  }
320 
321  if (avctx->pix_fmt == AV_PIX_FMT_BGR24 &&
322  ((frame->linesize[0] + 3) & ~3) * avctx->height <= buf_size)
323  frame->linesize[0] = (frame->linesize[0] + 3) & ~3;
324 
325  if (context->flip)
326  flip(avctx, picture);
327 
328  if (avctx->codec_tag == MKTAG('Y', 'V', '1', '2') ||
329  avctx->codec_tag == MKTAG('Y', 'V', '1', '6') ||
330  avctx->codec_tag == MKTAG('Y', 'V', '2', '4') ||
331  avctx->codec_tag == MKTAG('Y', 'V', 'U', '9'))
332  FFSWAP(uint8_t *, picture->data[1], picture->data[2]);
333 
334  if (avctx->codec_tag == AV_RL32("I420") && (avctx->width+1)*(avctx->height+1) * 3/2 == buf_size) {
335  picture->data[1] = picture->data[1] + (avctx->width+1)*(avctx->height+1) -avctx->width*avctx->height;
336  picture->data[2] = picture->data[2] + ((avctx->width+1)*(avctx->height+1) -avctx->width*avctx->height)*5/4;
337  }
338 
339  if (avctx->codec_tag == AV_RL32("yuv2") &&
340  avctx->pix_fmt == AV_PIX_FMT_YUYV422) {
341  int x, y;
342  uint8_t *line = picture->data[0];
343  for (y = 0; y < avctx->height; y++) {
344  for (x = 0; x < avctx->width; x++)
345  line[2 * x + 1] ^= 0x80;
346  line += picture->linesize[0];
347  }
348  }
349 
350  if (avctx->field_order > AV_FIELD_PROGRESSIVE) { /* we have interlaced material flagged in container */
351  frame->interlaced_frame = 1;
352  if (avctx->field_order == AV_FIELD_TT || avctx->field_order == AV_FIELD_TB)
353  frame->top_field_first = 1;
354  }
355 
356  *got_frame = 1;
357  return buf_size;
358 }
359 
360 static av_cold int raw_close_decoder(AVCodecContext *avctx)
361 {
362  RawVideoContext *context = avctx->priv_data;
363 
364  av_buffer_unref(&context->palette);
365  return 0;
366 }
367 
368 AVCodec ff_rawvideo_decoder = {
369  .name = "rawvideo",
370  .long_name = NULL_IF_CONFIG_SMALL("raw video"),
371  .type = AVMEDIA_TYPE_VIDEO,
372  .id = AV_CODEC_ID_RAWVIDEO,
373  .priv_data_size = sizeof(RawVideoContext),
374  .init = raw_init_decoder,
375  .close = raw_close_decoder,
376  .decode = raw_decode,
377  .priv_class = &rawdec_class,
378 };
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