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cdxl.c
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1 /*
2  * CDXL video decoder
3  * Copyright (c) 2011-2012 Paul B Mahol
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  * Commodore CDXL video decoder
25  * @author Paul B Mahol
26  */
27 
28 #define UNCHECKED_BITSTREAM_READER 1
29 
30 #include "libavutil/intreadwrite.h"
31 #include "libavutil/imgutils.h"
32 #include "avcodec.h"
33 #include "get_bits.h"
34 #include "internal.h"
35 
36 #define BIT_PLANAR 0x00
37 #define CHUNKY 0x20
38 #define BYTE_PLANAR 0x40
39 #define BIT_LINE 0x80
40 #define BYTE_LINE 0xC0
41 
42 typedef struct {
44  int bpp;
45  int format;
47  const uint8_t *palette;
49  const uint8_t *video;
54 
56 {
57  CDXLVideoContext *c = avctx->priv_data;
58 
59  c->new_video_size = 0;
60  c->avctx = avctx;
61 
62  return 0;
63 }
64 
65 static void import_palette(CDXLVideoContext *c, uint32_t *new_palette)
66 {
67  int i;
68 
69  for (i = 0; i < c->palette_size / 2; i++) {
70  unsigned rgb = AV_RB16(&c->palette[i * 2]);
71  unsigned r = ((rgb >> 8) & 0xF) * 0x11;
72  unsigned g = ((rgb >> 4) & 0xF) * 0x11;
73  unsigned b = (rgb & 0xF) * 0x11;
74  AV_WN32(&new_palette[i], (0xFFU << 24) | (r << 16) | (g << 8) | b);
75  }
76 }
77 
78 static void bitplanar2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)
79 {
80  GetBitContext gb;
81  int x, y, plane;
82 
83  init_get_bits(&gb, c->video, c->video_size * 8);
84  for (plane = 0; plane < c->bpp; plane++) {
85  for (y = 0; y < c->avctx->height; y++) {
86  for (x = 0; x < c->avctx->width; x++)
87  out[linesize * y + x] |= get_bits1(&gb) << plane;
88  skip_bits(&gb, c->padded_bits);
89  }
90  }
91 }
92 
93 static void bitline2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)
94 {
95  GetBitContext gb;
96  int x, y, plane;
97 
98  init_get_bits(&gb, c->video, c->video_size * 8);
99  for (y = 0; y < c->avctx->height; y++) {
100  for (plane = 0; plane < c->bpp; plane++) {
101  for (x = 0; x < c->avctx->width; x++)
102  out[linesize * y + x] |= get_bits1(&gb) << plane;
103  skip_bits(&gb, c->padded_bits);
104  }
105  }
106 }
107 
108 static void import_format(CDXLVideoContext *c, int linesize, uint8_t *out)
109 {
110  memset(out, 0, linesize * c->avctx->height);
111 
112  switch (c->format) {
113  case BIT_PLANAR:
114  bitplanar2chunky(c, linesize, out);
115  break;
116  case BIT_LINE:
117  bitline2chunky(c, linesize, out);
118  break;
119  }
120 }
121 
123 {
124  uint32_t *new_palette = (uint32_t *)frame->data[1];
125 
126  memset(frame->data[1], 0, AVPALETTE_SIZE);
127  import_palette(c, new_palette);
128  import_format(c, frame->linesize[0], frame->data[0]);
129 }
130 
132 {
133  AVCodecContext *avctx = c->avctx;
134  uint32_t new_palette[16], r, g, b;
135  uint8_t *ptr, *out, index, op;
136  int x, y;
137 
138  ptr = c->new_video;
139  out = frame->data[0];
140 
141  import_palette(c, new_palette);
142  import_format(c, avctx->width, c->new_video);
143 
144  for (y = 0; y < avctx->height; y++) {
145  r = new_palette[0] & 0xFF0000;
146  g = new_palette[0] & 0xFF00;
147  b = new_palette[0] & 0xFF;
148  for (x = 0; x < avctx->width; x++) {
149  index = *ptr++;
150  op = index >> 4;
151  index &= 15;
152  switch (op) {
153  case 0:
154  r = new_palette[index] & 0xFF0000;
155  g = new_palette[index] & 0xFF00;
156  b = new_palette[index] & 0xFF;
157  break;
158  case 1:
159  b = index * 0x11;
160  break;
161  case 2:
162  r = index * 0x11 << 16;
163  break;
164  case 3:
165  g = index * 0x11 << 8;
166  break;
167  }
168  AV_WL24(out + x * 3, r | g | b);
169  }
170  out += frame->linesize[0];
171  }
172 }
173 
175 {
176  AVCodecContext *avctx = c->avctx;
177  uint32_t new_palette[64], r, g, b;
178  uint8_t *ptr, *out, index, op;
179  int x, y;
180 
181  ptr = c->new_video;
182  out = frame->data[0];
183 
184  import_palette(c, new_palette);
185  import_format(c, avctx->width, c->new_video);
186 
187  for (y = 0; y < avctx->height; y++) {
188  r = new_palette[0] & 0xFF0000;
189  g = new_palette[0] & 0xFF00;
190  b = new_palette[0] & 0xFF;
191  for (x = 0; x < avctx->width; x++) {
192  index = *ptr++;
193  op = index >> 6;
194  index &= 63;
195  switch (op) {
196  case 0:
197  r = new_palette[index] & 0xFF0000;
198  g = new_palette[index] & 0xFF00;
199  b = new_palette[index] & 0xFF;
200  break;
201  case 1:
202  b = (index << 2) | (b & 3);
203  break;
204  case 2:
205  r = (index << 18) | (r & (3 << 16));
206  break;
207  case 3:
208  g = (index << 10) | (g & (3 << 8));
209  break;
210  }
211  AV_WL24(out + x * 3, r | g | b);
212  }
213  out += frame->linesize[0];
214  }
215 }
216 
217 static int cdxl_decode_frame(AVCodecContext *avctx, void *data,
218  int *got_frame, AVPacket *pkt)
219 {
220  CDXLVideoContext *c = avctx->priv_data;
221  AVFrame * const p = data;
222  int ret, w, h, encoding, aligned_width, buf_size = pkt->size;
223  const uint8_t *buf = pkt->data;
224 
225  if (buf_size < 32)
226  return AVERROR_INVALIDDATA;
227  encoding = buf[1] & 7;
228  c->format = buf[1] & 0xE0;
229  w = AV_RB16(&buf[14]);
230  h = AV_RB16(&buf[16]);
231  c->bpp = buf[19];
232  c->palette_size = AV_RB16(&buf[20]);
233  c->palette = buf + 32;
234  c->video = c->palette + c->palette_size;
235  c->video_size = buf_size - c->palette_size - 32;
236 
237  if (c->palette_size > 512)
238  return AVERROR_INVALIDDATA;
239  if (buf_size < c->palette_size + 32)
240  return AVERROR_INVALIDDATA;
241  if (c->bpp < 1)
242  return AVERROR_INVALIDDATA;
243  if (c->format != BIT_PLANAR && c->format != BIT_LINE) {
244  avpriv_request_sample(avctx, "Pixel format 0x%0x", c->format);
245  return AVERROR_PATCHWELCOME;
246  }
247 
248  if ((ret = av_image_check_size(w, h, 0, avctx)) < 0)
249  return ret;
250  if (w != avctx->width || h != avctx->height)
251  avcodec_set_dimensions(avctx, w, h);
252 
253  aligned_width = FFALIGN(c->avctx->width, 16);
254  c->padded_bits = aligned_width - c->avctx->width;
255  if (c->video_size < aligned_width * avctx->height * c->bpp / 8)
256  return AVERROR_INVALIDDATA;
257  if (!encoding && c->palette_size && c->bpp <= 8) {
258  avctx->pix_fmt = AV_PIX_FMT_PAL8;
259  } else if (encoding == 1 && (c->bpp == 6 || c->bpp == 8)) {
260  if (c->palette_size != (1 << (c->bpp - 1)))
261  return AVERROR_INVALIDDATA;
262  avctx->pix_fmt = AV_PIX_FMT_BGR24;
263  } else {
264  avpriv_request_sample(avctx, "Encoding %d and bpp %d",
265  encoding, c->bpp);
266  return AVERROR_PATCHWELCOME;
267  }
268 
269  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
270  return ret;
272 
273  if (encoding) {
276  if (!c->new_video)
277  return AVERROR(ENOMEM);
278  if (c->bpp == 8)
279  cdxl_decode_ham8(c, p);
280  else
281  cdxl_decode_ham6(c, p);
282  } else {
283  cdxl_decode_rgb(c, p);
284  }
285  *got_frame = 1;
286 
287  return buf_size;
288 }
289 
291 {
292  CDXLVideoContext *c = avctx->priv_data;
293 
294  av_freep(&c->new_video);
295 
296  return 0;
297 }
298 
300  .name = "cdxl",
301  .long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),
302  .type = AVMEDIA_TYPE_VIDEO,
303  .id = AV_CODEC_ID_CDXL,
304  .priv_data_size = sizeof(CDXLVideoContext),
308  .capabilities = CODEC_CAP_DR1,
309 };