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motionpixels.c
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1 /*
2  * Motion Pixels Video Decoder
3  * Copyright (c) 2008 Gregory Montoir (cyx@users.sourceforge.net)
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 "avcodec.h"
23 #include "get_bits.h"
24 #include "dsputil.h"
25 
26 #define MAX_HUFF_CODES 16
27 
28 #include "motionpixels_tablegen.h"
29 
30 typedef struct HuffCode {
31  int code;
34 } HuffCode;
35 
36 typedef struct MotionPixelsContext {
51 
53 {
54  MotionPixelsContext *mp = avctx->priv_data;
55  int w4 = (avctx->width + 3) & ~3;
56  int h4 = (avctx->height + 3) & ~3;
57 
58  if(avctx->extradata_size < 2){
59  av_log(avctx, AV_LOG_ERROR, "extradata too small\n");
60  return AVERROR_INVALIDDATA;
61  }
62 
64  mp->avctx = avctx;
65  ff_dsputil_init(&mp->dsp, avctx);
66  mp->changes_map = av_mallocz(avctx->width * h4);
67  mp->offset_bits_len = av_log2(avctx->width * avctx->height) + 1;
68  mp->vpt = av_mallocz(avctx->height * sizeof(YuvPixel));
69  mp->hpt = av_mallocz(h4 * w4 / 16 * sizeof(YuvPixel));
70  avctx->pix_fmt = AV_PIX_FMT_RGB555;
72  return 0;
73 }
74 
75 static void mp_read_changes_map(MotionPixelsContext *mp, GetBitContext *gb, int count, int bits_len, int read_color)
76 {
77  uint16_t *pixels;
78  int offset, w, h, color = 0, x, y, i;
79 
80  while (count--) {
81  offset = get_bits_long(gb, mp->offset_bits_len);
82  w = get_bits(gb, bits_len) + 1;
83  h = get_bits(gb, bits_len) + 1;
84  if (read_color)
85  color = get_bits(gb, 15);
86  x = offset % mp->avctx->width;
87  y = offset / mp->avctx->width;
88  if (y >= mp->avctx->height)
89  continue;
90  w = FFMIN(w, mp->avctx->width - x);
91  h = FFMIN(h, mp->avctx->height - y);
92  pixels = (uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2];
93  while (h--) {
94  mp->changes_map[offset] = w;
95  if (read_color)
96  for (i = 0; i < w; ++i)
97  pixels[i] = color;
98  offset += mp->avctx->width;
99  pixels += mp->frame.linesize[0] / 2;
100  }
101  }
102 }
103 
104 static int mp_get_code(MotionPixelsContext *mp, GetBitContext *gb, int size, int code)
105 {
106  while (get_bits1(gb)) {
107  ++size;
108  if (size > mp->max_codes_bits) {
109  av_log(mp->avctx, AV_LOG_ERROR, "invalid code size %d/%d\n", size, mp->max_codes_bits);
110  return AVERROR_INVALIDDATA;
111  }
112  code <<= 1;
113  if (mp_get_code(mp, gb, size, code + 1) < 0)
114  return AVERROR_INVALIDDATA;
115  }
116  if (mp->current_codes_count >= MAX_HUFF_CODES) {
117  av_log(mp->avctx, AV_LOG_ERROR, "too many codes\n");
118  return AVERROR_INVALIDDATA;
119  }
120 
121  mp->codes[mp->current_codes_count ].code = code;
122  mp->codes[mp->current_codes_count++].size = size;
123  return 0;
124 }
125 
127 {
128  if (mp->codes_count == 1) {
129  mp->codes[0].delta = get_bits(gb, 4);
130  } else {
131  int i;
132  int ret;
133 
134  mp->max_codes_bits = get_bits(gb, 4);
135  for (i = 0; i < mp->codes_count; ++i)
136  mp->codes[i].delta = get_bits(gb, 4);
137  mp->current_codes_count = 0;
138  if ((ret = mp_get_code(mp, gb, 0, 0)) < 0)
139  return ret;
140  if (mp->current_codes_count < mp->codes_count) {
141  av_log(mp->avctx, AV_LOG_ERROR, "too few codes\n");
142  return AVERROR_INVALIDDATA;
143  }
144  }
145  return 0;
146 }
147 
148 static int mp_gradient(MotionPixelsContext *mp, int component, int v)
149 {
150  int delta;
151 
152  delta = (v - 7) * mp->gradient_scale[component];
153  mp->gradient_scale[component] = (v == 0 || v == 14) ? 2 : 1;
154  return delta;
155 }
156 
158 {
159  int color;
160 
161  color = *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2];
162  return mp_rgb_yuv_table[color];
163 }
164 
165 static void mp_set_rgb_from_yuv(MotionPixelsContext *mp, int x, int y, const YuvPixel *p)
166 {
167  int color;
168 
169  color = mp_yuv_to_rgb(p->y, p->v, p->u, 1);
170  *(uint16_t *)&mp->frame.data[0][y * mp->frame.linesize[0] + x * 2] = color;
171 }
172 
174 {
175  int i;
176 
177  i = (mp->codes_count == 1) ? 0 : get_vlc2(gb, mp->vlc.table, mp->max_codes_bits, 1);
178  return mp->codes[i].delta;
179 }
180 
182 {
183  YuvPixel p;
184  const int y0 = y * mp->avctx->width;
185  int w, i, x = 0;
186 
187  p = mp->vpt[y];
188  if (mp->changes_map[y0 + x] == 0) {
189  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
190  ++x;
191  }
192  while (x < mp->avctx->width) {
193  w = mp->changes_map[y0 + x];
194  if (w != 0) {
195  if ((y & 3) == 0) {
196  if (mp->changes_map[y0 + x + mp->avctx->width] < w ||
197  mp->changes_map[y0 + x + mp->avctx->width * 2] < w ||
198  mp->changes_map[y0 + x + mp->avctx->width * 3] < w) {
199  for (i = (x + 3) & ~3; i < x + w; i += 4) {
200  mp->hpt[((y / 4) * mp->avctx->width + i) / 4] = mp_get_yuv_from_rgb(mp, i, y);
201  }
202  }
203  }
204  x += w;
205  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
206  p = mp_get_yuv_from_rgb(mp, x - 1, y);
207  } else {
208  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
209  p.y = av_clip(p.y, 0, 31);
210  if ((x & 3) == 0) {
211  if ((y & 3) == 0) {
212  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
213  p.v = av_clip(p.v, -32, 31);
214  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
215  p.u = av_clip(p.u, -32, 31);
216  mp->hpt[((y / 4) * mp->avctx->width + x) / 4] = p;
217  } else {
218  p.v = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].v;
219  p.u = mp->hpt[((y / 4) * mp->avctx->width + x) / 4].u;
220  }
221  }
222  mp_set_rgb_from_yuv(mp, x, y, &p);
223  ++x;
224  }
225  }
226 }
227 
229 {
230  YuvPixel p;
231  int y, y0;
232 
233  av_assert1(mp->changes_map[0]);
234 
235  for (y = 0; y < mp->avctx->height; ++y) {
236  if (mp->changes_map[y * mp->avctx->width] != 0) {
237  memset(mp->gradient_scale, 1, sizeof(mp->gradient_scale));
238  p = mp_get_yuv_from_rgb(mp, 0, y);
239  } else {
240  p.y += mp_gradient(mp, 0, mp_get_vlc(mp, gb));
241  p.y = av_clip(p.y, 0, 31);
242  if ((y & 3) == 0) {
243  p.v += mp_gradient(mp, 1, mp_get_vlc(mp, gb));
244  p.v = av_clip(p.v, -32, 31);
245  p.u += mp_gradient(mp, 2, mp_get_vlc(mp, gb));
246  p.u = av_clip(p.u, -32, 31);
247  }
248  mp->vpt[y] = p;
249  mp_set_rgb_from_yuv(mp, 0, y, &p);
250  }
251  }
252  for (y0 = 0; y0 < 2; ++y0)
253  for (y = y0; y < mp->avctx->height; y += 2)
254  mp_decode_line(mp, gb, y);
255 }
256 
257 static int mp_decode_frame(AVCodecContext *avctx,
258  void *data, int *got_frame,
259  AVPacket *avpkt)
260 {
261  const uint8_t *buf = avpkt->data;
262  int buf_size = avpkt->size;
263  MotionPixelsContext *mp = avctx->priv_data;
264  GetBitContext gb;
265  int i, count1, count2, sz, ret;
266 
267  mp->frame.reference = 3;
269  if ((ret = avctx->reget_buffer(avctx, &mp->frame)) < 0) {
270  av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
271  return ret;
272  }
273 
274  /* le32 bitstream msb first */
276  if (!mp->bswapbuf)
277  return AVERROR(ENOMEM);
278  mp->dsp.bswap_buf((uint32_t *)mp->bswapbuf, (const uint32_t *)buf, buf_size / 4);
279  if (buf_size & 3)
280  memcpy(mp->bswapbuf + (buf_size & ~3), buf + (buf_size & ~3), buf_size & 3);
281  memset(mp->bswapbuf + buf_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
282  init_get_bits(&gb, mp->bswapbuf, buf_size * 8);
283 
284  memset(mp->changes_map, 0, avctx->width * avctx->height);
285  for (i = !(avctx->extradata[1] & 2); i < 2; ++i) {
286  count1 = get_bits(&gb, 12);
287  count2 = get_bits(&gb, 12);
288  mp_read_changes_map(mp, &gb, count1, 8, i);
289  mp_read_changes_map(mp, &gb, count2, 4, i);
290  }
291 
292  mp->codes_count = get_bits(&gb, 4);
293  if (mp->codes_count == 0)
294  goto end;
295 
296  if (mp->changes_map[0] == 0) {
297  *(uint16_t *)mp->frame.data[0] = get_bits(&gb, 15);
298  mp->changes_map[0] = 1;
299  }
300  if (mp_read_codes_table(mp, &gb) < 0)
301  goto end;
302 
303  sz = get_bits(&gb, 18);
304  if (avctx->extradata[0] != 5)
305  sz += get_bits(&gb, 18);
306  if (sz == 0)
307  goto end;
308 
309  if (mp->max_codes_bits <= 0)
310  goto end;
311  if (init_vlc(&mp->vlc, mp->max_codes_bits, mp->codes_count, &mp->codes[0].size, sizeof(HuffCode), 1, &mp->codes[0].code, sizeof(HuffCode), 4, 0))
312  goto end;
313  mp_decode_frame_helper(mp, &gb);
314  ff_free_vlc(&mp->vlc);
315 
316 end:
317  *got_frame = 1;
318  *(AVFrame *)data = mp->frame;
319  return buf_size;
320 }
321 
323 {
324  MotionPixelsContext *mp = avctx->priv_data;
325 
326  av_freep(&mp->changes_map);
327  av_freep(&mp->vpt);
328  av_freep(&mp->hpt);
329  av_freep(&mp->bswapbuf);
330  if (mp->frame.data[0])
331  avctx->release_buffer(avctx, &mp->frame);
332 
333  return 0;
334 }
335 
337  .name = "motionpixels",
338  .type = AVMEDIA_TYPE_VIDEO,
340  .priv_data_size = sizeof(MotionPixelsContext),
341  .init = mp_decode_init,
342  .close = mp_decode_end,
344  .capabilities = CODEC_CAP_DR1,
345  .long_name = NULL_IF_CONFIG_SMALL("Motion Pixels video"),
346 };