pictordec.c
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1 /*
2  * Pictor/PC Paint decoder
3  * Copyright (c) 2010 Peter Ross <pross@xvid.org>
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 
27 #include "libavutil/imgutils.h"
28 #include "avcodec.h"
29 #include "bytestream.h"
30 #include "cga_data.h"
31 #include "internal.h"
32 
33 typedef struct PicContext {
35  int width, height;
36  int nb_planes;
38 } PicContext;
39 
40 static void picmemset_8bpp(PicContext *s, int value, int run, int *x, int *y)
41 {
42  while (run > 0) {
43  uint8_t *d = s->frame.data[0] + *y * s->frame.linesize[0];
44  if (*x + run >= s->width) {
45  int n = s->width - *x;
46  memset(d + *x, value, n);
47  run -= n;
48  *x = 0;
49  *y -= 1;
50  if (*y < 0)
51  break;
52  } else {
53  memset(d + *x, value, run);
54  *x += run;
55  break;
56  }
57  }
58 }
59 
60 static void picmemset(PicContext *s, int value, int run,
61  int *x, int *y, int *plane, int bits_per_plane)
62 {
63  uint8_t *d;
64  int shift = *plane * bits_per_plane;
65  int mask = ((1 << bits_per_plane) - 1) << shift;
66  value <<= shift;
67 
68  while (run > 0) {
69  int j;
70  for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
71  d = s->frame.data[0] + *y * s->frame.linesize[0];
72  d[*x] |= (value >> j) & mask;
73  *x += 1;
74  if (*x == s->width) {
75  *y -= 1;
76  *x = 0;
77  if (*y < 0) {
78  *y = s->height - 1;
79  *plane += 1;
80  value <<= bits_per_plane;
81  mask <<= bits_per_plane;
82  if (*plane >= s->nb_planes)
83  break;
84  }
85  }
86  }
87  run--;
88  }
89 }
90 
91 static const uint8_t cga_mode45_index[6][4] = {
92  [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity
93  [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity
94  [2] = { 0, 3, 4, 7 }, // mode5, low intensity
95  [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity
96  [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity
97  [5] = { 0, 11, 12, 15 }, // mode5, high intensity
98 };
99 
100 static int decode_frame(AVCodecContext *avctx,
101  void *data, int *got_frame,
102  AVPacket *avpkt)
103 {
104  PicContext *s = avctx->priv_data;
105  uint32_t *palette;
106  int bits_per_plane, bpp, etype, esize, npal, pos_after_pal;
107  int i, x, y, plane, tmp;
108 
109  bytestream2_init(&s->g, avpkt->data, avpkt->size);
110 
111  if (bytestream2_get_bytes_left(&s->g) < 11)
112  return AVERROR_INVALIDDATA;
113 
114  if (bytestream2_get_le16u(&s->g) != 0x1234)
115  return AVERROR_INVALIDDATA;
116 
117  s->width = bytestream2_get_le16u(&s->g);
118  s->height = bytestream2_get_le16u(&s->g);
119  bytestream2_skip(&s->g, 4);
120  tmp = bytestream2_get_byteu(&s->g);
121  bits_per_plane = tmp & 0xF;
122  s->nb_planes = (tmp >> 4) + 1;
123  bpp = bits_per_plane * s->nb_planes;
124  if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
125  av_log_ask_for_sample(avctx, "unsupported bit depth\n");
126  return AVERROR_PATCHWELCOME;
127  }
128 
129  if (bytestream2_peek_byte(&s->g) == 0xFF) {
130  bytestream2_skip(&s->g, 2);
131  etype = bytestream2_get_le16(&s->g);
132  esize = bytestream2_get_le16(&s->g);
133  if (bytestream2_get_bytes_left(&s->g) < esize)
134  return AVERROR_INVALIDDATA;
135  } else {
136  etype = -1;
137  esize = 0;
138  }
139 
140  avctx->pix_fmt = AV_PIX_FMT_PAL8;
141 
142  if (s->width != avctx->width && s->height != avctx->height) {
143  if (av_image_check_size(s->width, s->height, 0, avctx) < 0)
144  return -1;
145  avcodec_set_dimensions(avctx, s->width, s->height);
146  if (s->frame.data[0])
147  avctx->release_buffer(avctx, &s->frame);
148  }
149 
150  if (ff_get_buffer(avctx, &s->frame) < 0){
151  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
152  return -1;
153  }
154  memset(s->frame.data[0], 0, s->height * s->frame.linesize[0]);
156  s->frame.palette_has_changed = 1;
157 
158  pos_after_pal = bytestream2_tell(&s->g) + esize;
159  palette = (uint32_t*)s->frame.data[1];
160  if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) {
161  int idx = bytestream2_get_byte(&s->g);
162  npal = 4;
163  for (i = 0; i < npal; i++)
164  palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
165  } else if (etype == 2) {
166  npal = FFMIN(esize, 16);
167  for (i = 0; i < npal; i++) {
168  int pal_idx = bytestream2_get_byte(&s->g);
169  palette[i] = ff_cga_palette[FFMIN(pal_idx, 16)];
170  }
171  } else if (etype == 3) {
172  npal = FFMIN(esize, 16);
173  for (i = 0; i < npal; i++) {
174  int pal_idx = bytestream2_get_byte(&s->g);
175  palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)];
176  }
177  } else if (etype == 4 || etype == 5) {
178  npal = FFMIN(esize / 3, 256);
179  for (i = 0; i < npal; i++)
180  palette[i] = bytestream2_get_be24(&s->g) << 2;
181  } else {
182  if (bpp == 1) {
183  npal = 2;
184  palette[0] = 0x000000;
185  palette[1] = 0xFFFFFF;
186  } else if (bpp == 2) {
187  npal = 4;
188  for (i = 0; i < npal; i++)
189  palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
190  } else {
191  npal = 16;
192  memcpy(palette, ff_cga_palette, npal * 4);
193  }
194  }
195  // fill remaining palette entries
196  memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
197  // skip remaining palette bytes
198  bytestream2_seek(&s->g, pos_after_pal, SEEK_SET);
199 
200  x = 0;
201  y = s->height - 1;
202  plane = 0;
203  if (bytestream2_get_le16(&s->g)) {
204  while (bytestream2_get_bytes_left(&s->g) >= 6) {
205  int stop_size, marker, t1, t2;
206 
207  t1 = bytestream2_get_bytes_left(&s->g);
208  t2 = bytestream2_get_le16(&s->g);
209  stop_size = t1 - FFMIN(t1, t2);
210  // ignore uncompressed block size
211  bytestream2_skip(&s->g, 2);
212  marker = bytestream2_get_byte(&s->g);
213 
214  while (plane < s->nb_planes &&
215  bytestream2_get_bytes_left(&s->g) > stop_size) {
216  int run = 1;
217  int val = bytestream2_get_byte(&s->g);
218  if (val == marker) {
219  run = bytestream2_get_byte(&s->g);
220  if (run == 0)
221  run = bytestream2_get_le16(&s->g);
222  val = bytestream2_get_byte(&s->g);
223  }
224  if (!bytestream2_get_bytes_left(&s->g))
225  break;
226 
227  if (bits_per_plane == 8) {
228  picmemset_8bpp(s, val, run, &x, &y);
229  if (y < 0)
230  goto finish;
231  } else {
232  picmemset(s, val, run, &x, &y, &plane, bits_per_plane);
233  }
234  }
235  }
236  } else {
237  av_log_ask_for_sample(avctx, "uncompressed image\n");
238  return avpkt->size;
239  }
240 finish:
241 
242  *got_frame = 1;
243  *(AVFrame*)data = s->frame;
244  return avpkt->size;
245 }
246 
248 {
249  PicContext *s = avctx->priv_data;
250  if (s->frame.data[0])
251  avctx->release_buffer(avctx, &s->frame);
252  return 0;
253 }
254 
256  .name = "pictor",
257  .type = AVMEDIA_TYPE_VIDEO,
258  .id = AV_CODEC_ID_PICTOR,
259  .priv_data_size = sizeof(PicContext),
260  .close = decode_end,
261  .decode = decode_frame,
262  .capabilities = CODEC_CAP_DR1,
263  .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
264 };
This structure describes decoded (raw) audio or video data.
Definition: avcodec.h:989
void(* release_buffer)(struct AVCodecContext *c, AVFrame *pic)
Called to release buffers which were allocated with get_buffer.
Definition: avcodec.h:2259
misc image utilities
AVFrame frame
Definition: pictordec.c:34
int width
Definition: pictordec.c:35
void avcodec_set_dimensions(AVCodecContext *s, int width, int height)
Definition: utils.c:149
int size
Definition: avcodec.h:916
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1533
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:130
uint8_t run
Definition: svq3.c:132
AVCodec.
Definition: avcodec.h:2960
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:228
static const uint8_t cga_mode45_index[6][4]
Definition: pictordec.c:91
uint8_t
8 bit with PIX_FMT_RGB32 palette
Definition: pixfmt.h:76
static av_cold int decode_end(AVCodecContext *avctx)
Definition: pictordec.c:247
const char data[16]
Definition: mxf.c:66
uint8_t * data
Definition: avcodec.h:915
CGA/EGA/VGA ROM data.
GetByteContext g
Definition: pictordec.c:37
void av_log_ask_for_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message asking for a sample.
static const uint16_t mask[17]
Definition: lzw.c:38
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:159
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:88
#define t1
Definition: regdef.h:29
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:149
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:146
const char * name
Name of the codec implementation.
Definition: avcodec.h:2967
static void picmemset(PicContext *s, int value, int run, int *x, int *y, int *plane, int bits_per_plane)
Definition: pictordec.c:60
static void picmemset_8bpp(PicContext *s, int value, int run, int *x, int *y)
Definition: pictordec.c:40
int av_image_check_size(unsigned int w, unsigned int h, int log_offset, void *log_ctx)
Check if the given dimension of an image is valid, meaning that all bytes of the image can be address...
Definition: imgutils.c:220
enum AVPictureType pict_type
Picture type of the frame, see ?_TYPE below.
Definition: avcodec.h:1065
int width
picture width / height.
Definition: avcodec.h:1508
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame)
Get a buffer for a frame.
Definition: utils.c:464
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:183
external API header
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: pictordec.c:100
int linesize[AV_NUM_DATA_POINTERS]
Size, in bytes, of the data for each picture/channel plane.
Definition: avcodec.h:1008
main external API structure.
Definition: avcodec.h:1339
static void close(AVCodecParserContext *s)
Definition: h264_parser.c:326
AVCodec ff_pictor_decoder
Definition: pictordec.c:255
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: avcodec.h:1246
int height
Definition: pictordec.c:35
const uint32_t ff_cga_palette[16]
Definition: cga_data.c:419
const uint32_t ff_ega_palette[64]
Definition: cga_data.c:424
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: avcodec.h:997
common internal api header.
void * priv_data
Definition: avcodec.h:1382
struct PicContext PicContext
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:203
int nb_planes
Definition: pictordec.c:36
This structure stores compressed data.
Definition: avcodec.h:898
#define t2
Definition: regdef.h:30
if(!(ptr_align%ac->ptr_align)&&samples_align >=aligned_len)