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roqvideodec.c
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1 /*
2  * Copyright (C) 2003 the ffmpeg project
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 /**
22  * @file
23  * id RoQ Video Decoder by Dr. Tim Ferguson
24  * For more information about the id RoQ format, visit:
25  * http://www.csse.monash.edu.au/~timf/
26  */
27 
28 #include "libavutil/avassert.h"
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "roqvideo.h"
32 
33 static void roqvideo_decode_frame(RoqContext *ri)
34 {
35  unsigned int chunk_id = 0, chunk_arg = 0;
36  unsigned long chunk_size = 0;
37  int i, j, k, nv1, nv2, vqflg = 0, vqflg_pos = -1;
38  int vqid, xpos, ypos, xp, yp, x, y, mx, my;
39  int frame_stats[2][4] = {{0},{0}};
40  roq_qcell *qcell;
41  int64_t chunk_start;
42 
43  while (bytestream2_get_bytes_left(&ri->gb) >= 8) {
44  chunk_id = bytestream2_get_le16(&ri->gb);
45  chunk_size = bytestream2_get_le32(&ri->gb);
46  chunk_arg = bytestream2_get_le16(&ri->gb);
47 
48  if(chunk_id == RoQ_QUAD_VQ)
49  break;
50  if(chunk_id == RoQ_QUAD_CODEBOOK) {
51  if((nv1 = chunk_arg >> 8) == 0)
52  nv1 = 256;
53  if((nv2 = chunk_arg & 0xff) == 0 && nv1 * 6 < chunk_size)
54  nv2 = 256;
55  for(i = 0; i < nv1; i++) {
56  ri->cb2x2[i].y[0] = bytestream2_get_byte(&ri->gb);
57  ri->cb2x2[i].y[1] = bytestream2_get_byte(&ri->gb);
58  ri->cb2x2[i].y[2] = bytestream2_get_byte(&ri->gb);
59  ri->cb2x2[i].y[3] = bytestream2_get_byte(&ri->gb);
60  ri->cb2x2[i].u = bytestream2_get_byte(&ri->gb);
61  ri->cb2x2[i].v = bytestream2_get_byte(&ri->gb);
62  }
63  for(i = 0; i < nv2; i++)
64  for(j = 0; j < 4; j++)
65  ri->cb4x4[i].idx[j] = bytestream2_get_byte(&ri->gb);
66  }
67  }
68 
69  chunk_start = bytestream2_tell(&ri->gb);
70  xpos = ypos = 0;
71 
72  if (chunk_size > bytestream2_get_bytes_left(&ri->gb)) {
73  av_log(ri->avctx, AV_LOG_ERROR, "Chunk does not fit in input buffer\n");
74  chunk_size = bytestream2_get_bytes_left(&ri->gb);
75  }
76 
77  while (bytestream2_tell(&ri->gb) < chunk_start + chunk_size) {
78  for (yp = ypos; yp < ypos + 16; yp += 8)
79  for (xp = xpos; xp < xpos + 16; xp += 8) {
80  if (bytestream2_tell(&ri->gb) >= chunk_start + chunk_size) {
81  av_log(ri->avctx, AV_LOG_ERROR, "Input buffer too small\n");
82  return;
83  }
84  if (vqflg_pos < 0) {
85  vqflg = bytestream2_get_le16(&ri->gb);
86  vqflg_pos = 7;
87  }
88  vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
89  frame_stats[0][vqid]++;
90  vqflg_pos--;
91 
92  switch(vqid) {
93  case RoQ_ID_MOT:
94  break;
95  case RoQ_ID_FCC: {
96  int byte = bytestream2_get_byte(&ri->gb);
97  mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
98  my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
99  ff_apply_motion_8x8(ri, xp, yp, mx, my);
100  break;
101  }
102  case RoQ_ID_SLD:
103  qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
104  ff_apply_vector_4x4(ri, xp, yp, ri->cb2x2 + qcell->idx[0]);
105  ff_apply_vector_4x4(ri, xp + 4, yp, ri->cb2x2 + qcell->idx[1]);
106  ff_apply_vector_4x4(ri, xp, yp + 4, ri->cb2x2 + qcell->idx[2]);
107  ff_apply_vector_4x4(ri, xp + 4, yp + 4, ri->cb2x2 + qcell->idx[3]);
108  break;
109  case RoQ_ID_CCC:
110  for (k = 0; k < 4; k++) {
111  x = xp; y = yp;
112  if(k & 0x01) x += 4;
113  if(k & 0x02) y += 4;
114 
115  if (bytestream2_tell(&ri->gb) >= chunk_start + chunk_size) {
116  av_log(ri->avctx, AV_LOG_ERROR, "Input buffer too small\n");
117  return;
118  }
119  if (vqflg_pos < 0) {
120  vqflg = bytestream2_get_le16(&ri->gb);
121  vqflg_pos = 7;
122  }
123  vqid = (vqflg >> (vqflg_pos * 2)) & 0x3;
124  frame_stats[1][vqid]++;
125  vqflg_pos--;
126  switch(vqid) {
127  case RoQ_ID_MOT:
128  break;
129  case RoQ_ID_FCC: {
130  int byte = bytestream2_get_byte(&ri->gb);
131  mx = 8 - (byte >> 4) - ((signed char) (chunk_arg >> 8));
132  my = 8 - (byte & 0xf) - ((signed char) chunk_arg);
133  ff_apply_motion_4x4(ri, x, y, mx, my);
134  break;
135  }
136  case RoQ_ID_SLD:
137  qcell = ri->cb4x4 + bytestream2_get_byte(&ri->gb);
138  ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + qcell->idx[0]);
139  ff_apply_vector_2x2(ri, x + 2, y, ri->cb2x2 + qcell->idx[1]);
140  ff_apply_vector_2x2(ri, x, y + 2, ri->cb2x2 + qcell->idx[2]);
141  ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + qcell->idx[3]);
142  break;
143  case RoQ_ID_CCC:
144  ff_apply_vector_2x2(ri, x, y, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
145  ff_apply_vector_2x2(ri, x + 2, y, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
146  ff_apply_vector_2x2(ri, x, y + 2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
147  ff_apply_vector_2x2(ri, x + 2, y + 2, ri->cb2x2 + bytestream2_get_byte(&ri->gb));
148  break;
149  }
150  }
151  break;
152  default:
153  av_assert2(0);
154  }
155  }
156 
157  xpos += 16;
158  if (xpos >= ri->width) {
159  xpos -= ri->width;
160  ypos += 16;
161  }
162  if(ypos >= ri->height)
163  break;
164  }
165 }
166 
167 
168 static av_cold int roq_decode_init(AVCodecContext *avctx)
169 {
170  RoqContext *s = avctx->priv_data;
171 
172  s->avctx = avctx;
173 
174  if (avctx->width % 16 || avctx->height % 16) {
175  av_log(avctx, AV_LOG_ERROR,
176  "Dimensions must be a multiple of 16\n");
177  return AVERROR_PATCHWELCOME;
178  }
179 
180  s->width = avctx->width;
181  s->height = avctx->height;
182  avcodec_get_frame_defaults(&s->frames[0]);
183  avcodec_get_frame_defaults(&s->frames[1]);
184  s->last_frame = &s->frames[0];
185  s->current_frame = &s->frames[1];
186  avctx->pix_fmt = AV_PIX_FMT_YUV444P;
187 
188  return 0;
189 }
190 
191 static int roq_decode_frame(AVCodecContext *avctx,
192  void *data, int *got_frame,
193  AVPacket *avpkt)
194 {
195  const uint8_t *buf = avpkt->data;
196  int buf_size = avpkt->size;
197  RoqContext *s = avctx->priv_data;
198  int copy= !s->current_frame->data[0];
199  int ret;
200 
201  s->current_frame->reference = 3;
202  if ((ret = avctx->reget_buffer(avctx, s->current_frame)) < 0) {
203  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
204  return ret;
205  }
206 
207  if(copy)
208  av_picture_copy((AVPicture*)s->current_frame, (AVPicture*)s->last_frame,
209  avctx->pix_fmt, avctx->width, avctx->height);
210 
211  bytestream2_init(&s->gb, buf, buf_size);
212  roqvideo_decode_frame(s);
213 
214  *got_frame = 1;
215  *(AVFrame*)data = *s->current_frame;
216 
217  /* shuffle frames */
218  FFSWAP(AVFrame *, s->current_frame, s->last_frame);
219 
220  return buf_size;
221 }
222 
223 static av_cold int roq_decode_end(AVCodecContext *avctx)
224 {
225  RoqContext *s = avctx->priv_data;
226 
227  /* release the last frame */
228  if (s->last_frame->data[0])
229  avctx->release_buffer(avctx, s->last_frame);
230  if (s->current_frame->data[0])
231  avctx->release_buffer(avctx, s->current_frame);
232 
233  return 0;
234 }
235 
236 AVCodec ff_roq_decoder = {
237  .name = "roqvideo",
238  .type = AVMEDIA_TYPE_VIDEO,
239  .id = AV_CODEC_ID_ROQ,
240  .priv_data_size = sizeof(RoqContext),
241  .init = roq_decode_init,
242  .close = roq_decode_end,
243  .decode = roq_decode_frame,
244  .capabilities = CODEC_CAP_DR1,
245  .long_name = NULL_IF_CONFIG_SMALL("id RoQ video"),
246 };
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