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mvcdec.c
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1 /*
2  * Silicon Graphics Motion Video Compressor 1 & 2 decoder
3  * Copyright (c) 2012 Peter Ross
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  * Silicon Graphics Motion Video Compressor 1 & 2 decoder
25  */
26 
27 #include "libavutil/intreadwrite.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 
31 typedef struct MvcContext {
32  int vflip;
33 } MvcContext;
34 
36 {
37  MvcContext *s = avctx->priv_data;
38  int width = avctx->width;
39  int height = avctx->height;
40 
41  if (avctx->codec_id == AV_CODEC_ID_MVC1) {
42  width += 3;
43  height += 3;
44  }
45  width &= ~3;
46  height &= ~3;
47  if (width != avctx->width || height != avctx->height)
48  avcodec_set_dimensions(avctx, width, height);
49 
52  if (!avctx->coded_frame)
53  return AVERROR(ENOMEM);
54 
55  s->vflip = avctx->extradata_size >= 9 && !memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9);
56  return 0;
57 }
58 
59 static int decode_mvc1(AVCodecContext *avctx, GetByteContext *gb, uint8_t *dst_start, int width, int height, int linesize)
60 {
61  uint8_t *dst;
62  uint16_t v[8];
63  int mask, x, y, i;
64 
65  x = y= 0;
66  while (bytestream2_get_bytes_left(gb) >= 6) {
67  mask = bytestream2_get_be16u(gb);
68  v[0] = bytestream2_get_be16u(gb);
69  v[1] = bytestream2_get_be16u(gb);
70  if ((v[0] & 0x8000)) {
71  if (bytestream2_get_bytes_left(gb) < 12) {
72  av_log(avctx, AV_LOG_WARNING, "buffer overflow\n");
73  return AVERROR_INVALIDDATA;
74  }
75  for (i = 2; i < 8; i++)
76  v[i] = bytestream2_get_be16u(gb);
77  } else {
78  v[2] = v[4] = v[6] = v[0];
79  v[3] = v[5] = v[7] = v[1];
80  }
81 
82 #define PIX16(target, true, false) \
83  i = (mask & target) ? true : false; \
84  AV_WN16A(dst, (v[i] & 0x7C00) | (v[i] & 0x3E0) | (v[i] & 0x1F)); \
85  dst += 2;
86 
87 #define ROW16(row, a1, a0, b1, b0) \
88  dst = dst_start + (y + row) * linesize + x * 2; \
89  PIX16(1 << (row * 4), a1, a0) \
90  PIX16(1 << (row * 4 + 1), a1, a0) \
91  PIX16(1 << (row * 4 + 2), b1, b0) \
92  PIX16(1 << (row * 4 + 3), b1, b0)
93 
94  ROW16(0, 0, 1, 2, 3);
95  ROW16(1, 0, 1, 2, 3);
96  ROW16(2, 4, 5, 6, 7);
97  ROW16(3, 4, 5, 6, 7);
98 
99  x += 4;
100  if (x >= width) {
101  y += 4;
102  if (y >= height) {
103  break;
104  }
105  x = 0;
106  }
107  }
108  return 0;
109 }
110 
111 static void set_4x4_block(uint8_t *dst, int linesize, uint32_t pixel)
112 {
113  int i, j;
114  for (j = 0; j < 4; j++)
115  for (i = 0; i < 4; i++)
116  AV_WN32A(dst + j * linesize + i * 4, pixel);
117 }
118 
119 #define PIX32(target, true, false) \
120  AV_WN32A(dst, (mask & target) ? v[true] : v[false]); \
121  dst += 4;
122 
123 #define ROW32(row, a1, a0, b1, b0) \
124  dst = dst_start + (y + row) * linesize + x * 4; \
125  PIX32(1 << (row * 4), a1, a0) \
126  PIX32(1 << (row * 4 + 1), a1, a0) \
127  PIX32(1 << (row * 4 + 2), b1, b0) \
128  PIX32(1 << (row * 4 + 3), b1, b0)
129 
130 #define MVC2_BLOCK \
131  ROW32(0, 1, 0, 3, 2); \
132  ROW32(1, 1, 0, 3, 2); \
133  ROW32(2, 5, 4, 7, 6); \
134  ROW32(3, 5, 4, 7, 6);
135 
136 static int decode_mvc2(AVCodecContext *avctx, GetByteContext *gb, uint8_t *dst_start, int width, int height, int linesize, int vflip)
137 {
138  uint8_t *dst;
139  uint32_t color[128], v[8];
140  int w, h, nb_colors, i, x, y, p0, p1, mask;
141 
142  if (bytestream2_get_bytes_left(gb) < 6)
143  return AVERROR_INVALIDDATA;
144 
145  w = bytestream2_get_be16u(gb);
146  h = bytestream2_get_be16u(gb);
147  if ((w & ~3) != width || (h & ~3) != height)
148  av_log(avctx, AV_LOG_WARNING, "dimension mismatch\n");
149 
150  if (bytestream2_get_byteu(gb)) {
151  av_log_ask_for_sample(avctx, "bitmap feature\n");
152  return AVERROR_PATCHWELCOME;
153  }
154 
155  nb_colors = bytestream2_get_byteu(gb);
156  if (bytestream2_get_bytes_left(gb) < nb_colors * 3)
157  return AVERROR_INVALIDDATA;
158  for (i = 0; i < FFMIN(nb_colors, 128); i++)
159  color[i] = 0xFF000000 | bytestream2_get_be24u(gb);
160  if (nb_colors > 128)
161  bytestream2_skip(gb, (nb_colors - 128) * 3);
162 
163  if (vflip) {
164  dst_start += (height - 1) * linesize;
165  linesize = -linesize;
166  }
167  x = y = 0;
168  while (bytestream2_get_bytes_left(gb) >= 1) {
169  p0 = bytestream2_get_byteu(gb);
170  if ((p0 & 0x80)) {
171  if ((p0 & 0x40)) {
172  p0 &= 0x3F;
173  p0 = (p0 << 2) | (p0 >> 4);
174  set_4x4_block(dst_start + y * linesize + x * 4, linesize, 0xFF000000 | (p0 << 16) | (p0 << 8) | p0);
175  } else {
176  int g, r;
177  p0 &= 0x3F;
178  p0 = (p0 << 2) | (p0 >> 4);
179  if (bytestream2_get_bytes_left(gb) < 2)
180  return AVERROR_INVALIDDATA;
181  g = bytestream2_get_byteu(gb);
182  r = bytestream2_get_byteu(gb);
183  set_4x4_block(dst_start + y * linesize + x * 4, linesize, 0xFF000000 | (r << 16) | (g << 8) | p0);
184  }
185  } else {
186  if (bytestream2_get_bytes_left(gb) < 1)
187  return AVERROR_INVALIDDATA;
188  p1 = bytestream2_get_byteu(gb);
189  if ((p1 & 0x80)) {
190  if ((p0 & 0x7F) == (p1 & 0x7F)) {
191  set_4x4_block(dst_start + y * linesize + x * 4, linesize, color[p0 & 0x7F]);
192  } else {
193  if (bytestream2_get_bytes_left(gb) < 2)
194  return AVERROR_INVALIDDATA;
195  v[0] = v[2] = v[4] = v[6] = color[p0 & 0x7F];
196  v[1] = v[3] = v[5] = v[7] = color[p1 & 0x7F];
197  mask = bytestream2_get_le16u(gb);
198  MVC2_BLOCK
199  }
200  } else {
201  if (bytestream2_get_bytes_left(gb) < 8)
202  return AVERROR_INVALIDDATA;
203  v[0] = color[p0 & 0x7F];
204  v[1] = color[p1 & 0x7F];
205  for (i = 2; i < 8; i++)
206  v[i] = color[bytestream2_get_byteu(gb) & 0x7F];
207  mask = bytestream2_get_le16u(gb);
208  MVC2_BLOCK
209  }
210  }
211 
212  x += 4;
213  if (x >= width) {
214  y += 4;
215  if (y >= height)
216  break;
217  x = 0;
218  }
219  }
220  return 0;
221 }
222 
224  void *data, int *got_frame,
225  AVPacket *avpkt)
226 {
227  MvcContext *s = avctx->priv_data;
228  GetByteContext gb;
229  int ret;
230 
231  avctx->coded_frame->reference = 3;
234  ret = avctx->reget_buffer(avctx, avctx->coded_frame);
235  if (ret < 0) {
236  av_log (avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
237  return AVERROR(ENOMEM);
238  }
239 
240  bytestream2_init(&gb, avpkt->data, avpkt->size);
241  if (avctx->codec_id == AV_CODEC_ID_MVC1)
242  ret = decode_mvc1(avctx, &gb, avctx->coded_frame->data[0], avctx->width, avctx->height, avctx->coded_frame->linesize[0]);
243  else
244  ret = decode_mvc2(avctx, &gb, avctx->coded_frame->data[0], avctx->width, avctx->height, avctx->coded_frame->linesize[0], s->vflip);
245  if (ret < 0)
246  return ret;
247 
248  *got_frame = 1;
249  *(AVFrame*)data = *avctx->coded_frame;
250  return avpkt->size;
251 }
252 
254 {
255  if (avctx->coded_frame->data[0])
256  avctx->release_buffer(avctx, avctx->coded_frame);
257  av_freep(&avctx->coded_frame);
258  return 0;
259 }
260 
261 #if CONFIG_MVC1_DECODER
262 AVCodec ff_mvc1_decoder = {
263  .name = "mvc1",
264  .type = AVMEDIA_TYPE_VIDEO,
265  .id = AV_CODEC_ID_MVC1,
266  .priv_data_size = sizeof(MvcContext),
270  .capabilities = CODEC_CAP_DR1,
271  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video Compressor 1"),
272 };
273 #endif
274 
275 #if CONFIG_MVC2_DECODER
276 AVCodec ff_mvc2_decoder = {
277  .name = "mvc2",
278  .type = AVMEDIA_TYPE_VIDEO,
279  .id = AV_CODEC_ID_MVC2,
280  .priv_data_size = sizeof(MvcContext),
284  .capabilities = CODEC_CAP_DR1,
285  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video Compressor 2"),
286 };
287 #endif