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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 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "internal.h"
32 
33 typedef struct MvcContext {
34  AVFrame *frame;
35  int vflip;
36 } MvcContext;
37 
38 static av_cold int mvc_decode_init(AVCodecContext *avctx)
39 {
40  MvcContext *s = avctx->priv_data;
41  int width = avctx->width;
42  int height = avctx->height;
43  int ret;
44 
45  if (avctx->codec_id == AV_CODEC_ID_MVC1) {
46  width += 3;
47  height += 3;
48  }
49  width &= ~3;
50  height &= ~3;
51  if ((ret = ff_set_dimensions(avctx, width, height)) < 0)
52  return ret;
53 
54  avctx->pix_fmt = (avctx->codec_id == AV_CODEC_ID_MVC1) ? AV_PIX_FMT_RGB555
55  : AV_PIX_FMT_RGB32;
56  s->frame = av_frame_alloc();
57  if (!s->frame)
58  return AVERROR(ENOMEM);
59 
60  s->vflip = avctx->extradata_size >= 9 &&
61  !memcmp(avctx->extradata + avctx->extradata_size - 9, "BottomUp", 9);
62  return 0;
63 }
64 
65 static int decode_mvc1(AVCodecContext *avctx, GetByteContext *gb,
66  uint8_t *dst_start, int width, int height, int linesize)
67 {
68  uint8_t *dst;
69  uint16_t v[8];
70  int mask, x, y, i;
71 
72  for (y = 0; y < height; y += 4) {
73  for (x = 0; x < width; x += 4) {
74  if (bytestream2_get_bytes_left(gb) < 6)
75  return 0;
76 
77  mask = bytestream2_get_be16u(gb);
78  v[0] = bytestream2_get_be16u(gb);
79  v[1] = bytestream2_get_be16u(gb);
80  if ((v[0] & 0x8000)) {
81  if (bytestream2_get_bytes_left(gb) < 12) {
82  av_log(avctx, AV_LOG_WARNING, "buffer overflow\n");
83  return AVERROR_INVALIDDATA;
84  }
85  for (i = 2; i < 8; i++)
86  v[i] = bytestream2_get_be16u(gb);
87  } else {
88  v[2] = v[4] = v[6] = v[0];
89  v[3] = v[5] = v[7] = v[1];
90  }
91 
92 #define PIX16(target, true, false) \
93  i = (mask & target) ? true : false; \
94  AV_WN16A(dst, v[i] & 0x7FFF); \
95  dst += 2;
96 
97 #define ROW16(row, a1, a0, b1, b0) \
98  dst = dst_start + (y + row) * linesize + x * 2; \
99  PIX16(1 << (row * 4), a1, a0) \
100  PIX16(1 << (row * 4 + 1), a1, a0) \
101  PIX16(1 << (row * 4 + 2), b1, b0) \
102  PIX16(1 << (row * 4 + 3), b1, b0)
103 
104  ROW16(0, 0, 1, 2, 3);
105  ROW16(1, 0, 1, 2, 3);
106  ROW16(2, 4, 5, 6, 7);
107  ROW16(3, 4, 5, 6, 7);
108  }
109  }
110  return 0;
111 }
112 
113 static void set_4x4_block(uint8_t *dst, int linesize, uint32_t pixel)
114 {
115  int i, j;
116  for (j = 0; j < 4; j++)
117  for (i = 0; i < 4; i++)
118  AV_WN32A(dst + j * linesize + i * 4, pixel);
119 }
120 
121 #define PIX32(target, true, false) \
122  AV_WN32A(dst, (mask & target) ? v[true] : v[false]); \
123  dst += 4;
124 
125 #define ROW32(row, a1, a0, b1, b0) \
126  dst = dst_start + (y + row) * linesize + x * 4; \
127  PIX32(1 << (row * 4), a1, a0) \
128  PIX32(1 << (row * 4 + 1), a1, a0) \
129  PIX32(1 << (row * 4 + 2), b1, b0) \
130  PIX32(1 << (row * 4 + 3), b1, b0)
131 
132 #define MVC2_BLOCK \
133  ROW32(0, 1, 0, 3, 2); \
134  ROW32(1, 1, 0, 3, 2); \
135  ROW32(2, 5, 4, 7, 6); \
136  ROW32(3, 5, 4, 7, 6);
137 
138 static int decode_mvc2(AVCodecContext *avctx, GetByteContext *gb,
139  uint8_t *dst_start, int width, int height,
140  int linesize, int vflip)
141 {
142  uint8_t *dst;
143  uint32_t color[128], v[8];
144  int w, h, nb_colors, i, x, y, p0, p1, mask;
145 
146  if (bytestream2_get_bytes_left(gb) < 6)
147  return AVERROR_INVALIDDATA;
148 
149  w = bytestream2_get_be16u(gb);
150  h = bytestream2_get_be16u(gb);
151  if ((w & ~3) != width || (h & ~3) != height)
152  av_log(avctx, AV_LOG_WARNING, "dimension mismatch\n");
153 
154  if (bytestream2_get_byteu(gb)) {
155  avpriv_request_sample(avctx, "bitmap feature");
156  return AVERROR_PATCHWELCOME;
157  }
158 
159  nb_colors = bytestream2_get_byteu(gb);
160  if (bytestream2_get_bytes_left(gb) < nb_colors * 3)
161  return AVERROR_INVALIDDATA;
162  for (i = 0; i < FFMIN(nb_colors, 128); i++)
163  color[i] = 0xFF000000 | bytestream2_get_be24u(gb);
164  if (nb_colors > 128)
165  bytestream2_skip(gb, (nb_colors - 128) * 3);
166 
167  if (vflip) {
168  dst_start += (height - 1) * linesize;
169  linesize = -linesize;
170  }
171  x = y = 0;
172  while (bytestream2_get_bytes_left(gb) >= 1) {
173  p0 = bytestream2_get_byteu(gb);
174  if ((p0 & 0x80)) {
175  if ((p0 & 0x40)) {
176  p0 &= 0x3F;
177  p0 = (p0 << 2) | (p0 >> 4);
178  set_4x4_block(dst_start + y * linesize + x * 4, linesize,
179  0xFF000000 | (p0 << 16) | (p0 << 8) | p0);
180  } else {
181  int g, r;
182  p0 &= 0x3F;
183  p0 = (p0 << 2) | (p0 >> 4);
184  if (bytestream2_get_bytes_left(gb) < 2)
185  return AVERROR_INVALIDDATA;
186  g = bytestream2_get_byteu(gb);
187  r = bytestream2_get_byteu(gb);
188  set_4x4_block(dst_start + y * linesize + x * 4, linesize,
189  0xFF000000 | (r << 16) | (g << 8) | p0);
190  }
191  } else {
192  if (bytestream2_get_bytes_left(gb) < 1)
193  return AVERROR_INVALIDDATA;
194  p1 = bytestream2_get_byteu(gb);
195  if ((p1 & 0x80)) {
196  if ((p0 & 0x7F) == (p1 & 0x7F)) {
197  set_4x4_block(dst_start + y * linesize + x * 4, linesize,
198  color[p0 & 0x7F]);
199  } else {
200  if (bytestream2_get_bytes_left(gb) < 2)
201  return AVERROR_INVALIDDATA;
202  v[0] = v[2] = v[4] = v[6] = color[p0 & 0x7F];
203  v[1] = v[3] = v[5] = v[7] = color[p1 & 0x7F];
204  mask = bytestream2_get_le16u(gb);
205  MVC2_BLOCK
206  }
207  } else {
208  if (bytestream2_get_bytes_left(gb) < 8)
209  return AVERROR_INVALIDDATA;
210  v[0] = color[p0 & 0x7F];
211  v[1] = color[p1 & 0x7F];
212  for (i = 2; i < 8; i++)
213  v[i] = color[bytestream2_get_byteu(gb) & 0x7F];
214  mask = bytestream2_get_le16u(gb);
215  MVC2_BLOCK
216  }
217  }
218 
219  x += 4;
220  if (x >= width) {
221  y += 4;
222  if (y >= height)
223  break;
224  x = 0;
225  }
226  }
227  return 0;
228 }
229 
230 static int mvc_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
231  AVPacket *avpkt)
232 {
233  MvcContext *s = avctx->priv_data;
234  GetByteContext gb;
235  int ret;
236 
237  if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)
238  return ret;
239 
240  bytestream2_init(&gb, avpkt->data, avpkt->size);
241  if (avctx->codec_id == AV_CODEC_ID_MVC1)
242  ret = decode_mvc1(avctx, &gb, s->frame->data[0],
243  avctx->width, avctx->height, s->frame->linesize[0]);
244  else
245  ret = decode_mvc2(avctx, &gb, s->frame->data[0],
246  avctx->width, avctx->height, s->frame->linesize[0],
247  s->vflip);
248  if (ret < 0)
249  return ret;
250 
251  *got_frame = 1;
252  if ((ret = av_frame_ref(data, s->frame)) < 0)
253  return ret;
254 
255  return avpkt->size;
256 }
257 
258 static av_cold int mvc_decode_end(AVCodecContext *avctx)
259 {
260  MvcContext *s = avctx->priv_data;
261 
262  av_frame_free(&s->frame);
263 
264  return 0;
265 }
266 
267 #if CONFIG_MVC1_DECODER
268 AVCodec ff_mvc1_decoder = {
269  .name = "mvc1",
270  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video Compressor 1"),
271  .type = AVMEDIA_TYPE_VIDEO,
272  .id = AV_CODEC_ID_MVC1,
273  .priv_data_size = sizeof(MvcContext),
274  .init = mvc_decode_init,
275  .close = mvc_decode_end,
276  .decode = mvc_decode_frame,
277  .capabilities = CODEC_CAP_DR1,
278 };
279 #endif
280 
281 #if CONFIG_MVC2_DECODER
282 AVCodec ff_mvc2_decoder = {
283  .name = "mvc2",
284  .long_name = NULL_IF_CONFIG_SMALL("Silicon Graphics Motion Video Compressor 2"),
285  .type = AVMEDIA_TYPE_VIDEO,
286  .id = AV_CODEC_ID_MVC2,
287  .priv_data_size = sizeof(MvcContext),
288  .init = mvc_decode_init,
289  .close = mvc_decode_end,
290  .decode = mvc_decode_frame,
291  .capabilities = CODEC_CAP_DR1,
292 };
293 #endif
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