Libav
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 Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "libavutil/intreadwrite.h"
23 #include "libavutil/imgutils.h"
24 #include "avcodec.h"
25 #include "get_bits.h"
26 #include "internal.h"
27 
28 #define BIT_PLANAR 0x00
29 #define BYTE_PLANAR 0x20
30 #define CHUNKY 0x40
31 #define BIT_LINE 0x80
32 #define BYTE_LINE 0xC0
33 
34 typedef struct {
36  int bpp;
37  int format;
39  const uint8_t *palette;
41  const uint8_t *video;
46 
48 {
49  CDXLVideoContext *c = avctx->priv_data;
50 
51  c->new_video_size = 0;
52  c->avctx = avctx;
53 
54  return 0;
55 }
56 
57 static void import_palette(CDXLVideoContext *c, uint32_t *new_palette)
58 {
59  int i;
60 
61  for (i = 0; i < c->palette_size / 2; i++) {
62  unsigned rgb = AV_RB16(&c->palette[i * 2]);
63  unsigned r = ((rgb >> 8) & 0xF) * 0x11;
64  unsigned g = ((rgb >> 4) & 0xF) * 0x11;
65  unsigned b = (rgb & 0xF) * 0x11;
66  AV_WN32(&new_palette[i], (r << 16) | (g << 8) | b);
67  }
68 }
69 
70 static void bitplanar2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)
71 {
72  GetBitContext gb;
73  int x, y, plane;
74 
75  init_get_bits(&gb, c->video, c->video_size * 8);
76  for (plane = 0; plane < c->bpp; plane++) {
77  for (y = 0; y < c->avctx->height; y++) {
78  for (x = 0; x < c->avctx->width; x++)
79  out[linesize * y + x] |= get_bits1(&gb) << plane;
80  skip_bits(&gb, c->padded_bits);
81  }
82  }
83 }
84 
85 static void bitline2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)
86 {
87  GetBitContext gb;
88  int x, y, plane;
89 
90  init_get_bits(&gb, c->video, c->video_size * 8);
91  for (y = 0; y < c->avctx->height; y++) {
92  for (plane = 0; plane < c->bpp; plane++) {
93  for (x = 0; x < c->avctx->width; x++)
94  out[linesize * y + x] |= get_bits1(&gb) << plane;
95  skip_bits(&gb, c->padded_bits);
96  }
97  }
98 }
99 
100 static void import_format(CDXLVideoContext *c, int linesize, uint8_t *out)
101 {
102  memset(out, 0, linesize * c->avctx->height);
103 
104  switch (c->format) {
105  case BIT_PLANAR:
106  bitplanar2chunky(c, linesize, out);
107  break;
108  case BIT_LINE:
109  bitline2chunky(c, linesize, out);
110  break;
111  }
112 }
113 
114 static void cdxl_decode_rgb(CDXLVideoContext *c, AVFrame *frame)
115 {
116  uint32_t *new_palette = (uint32_t *)frame->data[1];
117 
118  import_palette(c, new_palette);
119  import_format(c, frame->linesize[0], frame->data[0]);
120 }
121 
123 {
124  AVCodecContext *avctx = c->avctx;
125  uint32_t new_palette[16], r, g, b;
126  uint8_t *ptr, *out, index, op;
127  int x, y;
128 
129  ptr = c->new_video;
130  out = frame->data[0];
131 
132  import_palette(c, new_palette);
133  import_format(c, avctx->width, c->new_video);
134 
135  for (y = 0; y < avctx->height; y++) {
136  r = new_palette[0] & 0xFF0000;
137  g = new_palette[0] & 0xFF00;
138  b = new_palette[0] & 0xFF;
139  for (x = 0; x < avctx->width; x++) {
140  index = *ptr++;
141  op = index >> 4;
142  index &= 15;
143  switch (op) {
144  case 0:
145  r = new_palette[index] & 0xFF0000;
146  g = new_palette[index] & 0xFF00;
147  b = new_palette[index] & 0xFF;
148  break;
149  case 1:
150  b = index * 0x11;
151  break;
152  case 2:
153  r = index * 0x11 << 16;
154  break;
155  case 3:
156  g = index * 0x11 << 8;
157  break;
158  }
159  AV_WL24(out + x * 3, r | g | b);
160  }
161  out += frame->linesize[0];
162  }
163 }
164 
166 {
167  AVCodecContext *avctx = c->avctx;
168  uint32_t new_palette[64], r, g, b;
169  uint8_t *ptr, *out, index, op;
170  int x, y;
171 
172  ptr = c->new_video;
173  out = frame->data[0];
174 
175  import_palette(c, new_palette);
176  import_format(c, avctx->width, c->new_video);
177 
178  for (y = 0; y < avctx->height; y++) {
179  r = new_palette[0] & 0xFF0000;
180  g = new_palette[0] & 0xFF00;
181  b = new_palette[0] & 0xFF;
182  for (x = 0; x < avctx->width; x++) {
183  index = *ptr++;
184  op = index >> 6;
185  index &= 63;
186  switch (op) {
187  case 0:
188  r = new_palette[index] & 0xFF0000;
189  g = new_palette[index] & 0xFF00;
190  b = new_palette[index] & 0xFF;
191  break;
192  case 1:
193  b = (index << 2) | (b & 3);
194  break;
195  case 2:
196  r = (index << 18) | (r & (3 << 16));
197  break;
198  case 3:
199  g = (index << 10) | (g & (3 << 8));
200  break;
201  }
202  AV_WL24(out + x * 3, r | g | b);
203  }
204  out += frame->linesize[0];
205  }
206 }
207 
208 static int cdxl_decode_frame(AVCodecContext *avctx, void *data,
209  int *got_frame, AVPacket *pkt)
210 {
211  CDXLVideoContext *c = avctx->priv_data;
212  AVFrame * const p = data;
213  int ret, w, h, encoding, aligned_width, buf_size = pkt->size;
214  const uint8_t *buf = pkt->data;
215 
216  if (buf_size < 32)
217  return AVERROR_INVALIDDATA;
218  encoding = buf[1] & 7;
219  c->format = buf[1] & 0xE0;
220  w = AV_RB16(&buf[14]);
221  h = AV_RB16(&buf[16]);
222  c->bpp = buf[19];
223  c->palette_size = AV_RB16(&buf[20]);
224  c->palette = buf + 32;
225  c->video = c->palette + c->palette_size;
226  c->video_size = buf_size - c->palette_size - 32;
227 
228  if (c->palette_size > 512)
229  return AVERROR_INVALIDDATA;
230  if (buf_size < c->palette_size + 32)
231  return AVERROR_INVALIDDATA;
232  if (c->bpp < 1)
233  return AVERROR_INVALIDDATA;
234  if (c->format != BIT_PLANAR && c->format != BIT_LINE) {
235  avpriv_request_sample(avctx, "Pixel format 0x%0x", c->format);
236  return AVERROR_PATCHWELCOME;
237  }
238 
239  if ((ret = ff_set_dimensions(avctx, w, h)) < 0)
240  return ret;
241 
242  aligned_width = FFALIGN(c->avctx->width, 16);
243  c->padded_bits = aligned_width - c->avctx->width;
244  if (c->video_size < aligned_width * avctx->height * c->bpp / 8)
245  return AVERROR_INVALIDDATA;
246  if (!encoding && c->palette_size && c->bpp <= 8) {
247  avctx->pix_fmt = AV_PIX_FMT_PAL8;
248  } else if (encoding == 1 && (c->bpp == 6 || c->bpp == 8)) {
249  if (c->palette_size != (1 << (c->bpp - 1)))
250  return AVERROR_INVALIDDATA;
251  avctx->pix_fmt = AV_PIX_FMT_BGR24;
252  } else {
253  avpriv_request_sample(avctx, "Encoding %d and bpp %d",
254  encoding, c->bpp);
255  return AVERROR_PATCHWELCOME;
256  }
257 
258  if ((ret = ff_get_buffer(avctx, p, 0)) < 0) {
259  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
260  return ret;
261  }
263 
264  if (encoding) {
267  if (!c->new_video)
268  return AVERROR(ENOMEM);
269  if (c->bpp == 8)
270  cdxl_decode_ham8(c, p);
271  else
272  cdxl_decode_ham6(c, p);
273  } else {
274  cdxl_decode_rgb(c, p);
275  }
276  *got_frame = 1;
277 
278  return buf_size;
279 }
280 
282 {
283  CDXLVideoContext *c = avctx->priv_data;
284 
285  av_free(c->new_video);
286 
287  return 0;
288 }
289 
291  .name = "cdxl",
292  .long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),
293  .type = AVMEDIA_TYPE_VIDEO,
294  .id = AV_CODEC_ID_CDXL,
295  .priv_data_size = sizeof(CDXLVideoContext),
299  .capabilities = CODEC_CAP_DR1,
300 };