Libav
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 {
34  int width, height;
35  int nb_planes;
37 } PicContext;
38 
39 static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run,
40  int *x, int *y)
41 {
42  while (run > 0) {
43  uint8_t *d = frame->data[0] + *y * 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, AVFrame *frame, 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 = frame->data[0] + *y * 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  AVFrame *frame = data;
106  uint32_t *palette;
107  int bits_per_plane, bpp, etype, esize, npal, pos_after_pal;
108  int i, x, y, plane, tmp, ret;
109 
110  bytestream2_init(&s->g, avpkt->data, avpkt->size);
111 
112  if (bytestream2_get_bytes_left(&s->g) < 11)
113  return AVERROR_INVALIDDATA;
114 
115  if (bytestream2_get_le16u(&s->g) != 0x1234)
116  return AVERROR_INVALIDDATA;
117 
118  s->width = bytestream2_get_le16u(&s->g);
119  s->height = bytestream2_get_le16u(&s->g);
120  bytestream2_skip(&s->g, 4);
121  tmp = bytestream2_get_byteu(&s->g);
122  bits_per_plane = tmp & 0xF;
123  s->nb_planes = (tmp >> 4) + 1;
124  bpp = bits_per_plane * s->nb_planes;
125  if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
126  avpriv_request_sample(avctx, "Unsupported bit depth");
127  return AVERROR_PATCHWELCOME;
128  }
129 
130  if (bytestream2_peek_byte(&s->g) == 0xFF) {
131  bytestream2_skip(&s->g, 2);
132  etype = bytestream2_get_le16(&s->g);
133  esize = bytestream2_get_le16(&s->g);
134  if (bytestream2_get_bytes_left(&s->g) < esize)
135  return AVERROR_INVALIDDATA;
136  } else {
137  etype = -1;
138  esize = 0;
139  }
140 
141  avctx->pix_fmt = AV_PIX_FMT_PAL8;
142 
143  if (s->width != avctx->width || s->height != avctx->height) {
144  ret = ff_set_dimensions(avctx, s->width, s->height);
145  if (ret < 0)
146  return ret;
147  }
148 
149  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
150  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
151  return ret;
152  }
153  memset(frame->data[0], 0, s->height * frame->linesize[0]);
154  frame->pict_type = AV_PICTURE_TYPE_I;
155  frame->palette_has_changed = 1;
156 
157  pos_after_pal = bytestream2_tell(&s->g) + esize;
158  palette = (uint32_t*)frame->data[1];
159  if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) {
160  int idx = bytestream2_get_byte(&s->g);
161  npal = 4;
162  for (i = 0; i < npal; i++)
163  palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
164  } else if (etype == 2) {
165  npal = FFMIN(esize, 16);
166  for (i = 0; i < npal; i++) {
167  int pal_idx = bytestream2_get_byte(&s->g);
168  palette[i] = ff_cga_palette[FFMIN(pal_idx, 16)];
169  }
170  } else if (etype == 3) {
171  npal = FFMIN(esize, 16);
172  for (i = 0; i < npal; i++) {
173  int pal_idx = bytestream2_get_byte(&s->g);
174  palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)];
175  }
176  } else if (etype == 4 || etype == 5) {
177  npal = FFMIN(esize / 3, 256);
178  for (i = 0; i < npal; i++)
179  palette[i] = bytestream2_get_be24(&s->g) << 2;
180  } else {
181  if (bpp == 1) {
182  npal = 2;
183  palette[0] = 0x000000;
184  palette[1] = 0xFFFFFF;
185  } else if (bpp == 2) {
186  npal = 4;
187  for (i = 0; i < npal; i++)
188  palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
189  } else {
190  npal = 16;
191  memcpy(palette, ff_cga_palette, npal * 4);
192  }
193  }
194  // fill remaining palette entries
195  memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
196  // skip remaining palette bytes
197  bytestream2_seek(&s->g, pos_after_pal, SEEK_SET);
198 
199  x = 0;
200  y = s->height - 1;
201  plane = 0;
202  if (bytestream2_get_le16(&s->g)) {
203  while (bytestream2_get_bytes_left(&s->g) >= 6) {
204  int stop_size, marker, t1, t2;
205 
206  t1 = bytestream2_get_bytes_left(&s->g);
207  t2 = bytestream2_get_le16(&s->g);
208  stop_size = t1 - FFMIN(t1, t2);
209  // ignore uncompressed block size
210  bytestream2_skip(&s->g, 2);
211  marker = bytestream2_get_byte(&s->g);
212 
213  while (plane < s->nb_planes &&
214  bytestream2_get_bytes_left(&s->g) > stop_size) {
215  int run = 1;
216  int val = bytestream2_get_byte(&s->g);
217  if (val == marker) {
218  run = bytestream2_get_byte(&s->g);
219  if (run == 0)
220  run = bytestream2_get_le16(&s->g);
221  val = bytestream2_get_byte(&s->g);
222  }
223  if (!bytestream2_get_bytes_left(&s->g))
224  break;
225 
226  if (bits_per_plane == 8) {
227  picmemset_8bpp(s, frame, val, run, &x, &y);
228  if (y < 0)
229  goto finish;
230  } else {
231  picmemset(s, frame, val, run, &x, &y, &plane, bits_per_plane);
232  }
233  }
234  }
235  } else {
236  avpriv_request_sample(avctx, "Uncompressed image");
237  return avpkt->size;
238  }
239 finish:
240 
241  *got_frame = 1;
242  return avpkt->size;
243 }
244 
246  .name = "pictor",
247  .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
248  .type = AVMEDIA_TYPE_VIDEO,
249  .id = AV_CODEC_ID_PICTOR,
250  .priv_data_size = sizeof(PicContext),
251  .decode = decode_frame,
252  .capabilities = CODEC_CAP_DR1,
253 };
#define AVPALETTE_SIZE
Definition: avcodec.h:3051
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:54
This structure describes decoded (raw) audio or video data.
Definition: frame.h:135
static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run, int *x, int *y)
Definition: pictordec.c:39
misc image utilities
int width
Definition: pictordec.c:34
int ff_set_dimensions(AVCodecContext *s, int width, int height)
Check that the provided frame dimensions are valid and set them on the codec context.
Definition: utils.c:133
int size
Definition: avcodec.h:974
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:1270
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:132
static void picmemset(PicContext *s, AVFrame *frame, int value, int run, int *x, int *y, int *plane, int bits_per_plane)
Definition: pictordec.c:60
uint8_t run
Definition: svq3.c:146
AVCodec.
Definition: avcodec.h:2812
static int decode(MimicContext *ctx, int quality, int num_coeffs, int is_iframe)
Definition: mimic.c:275
void void avpriv_request_sample(void *avc, const char *msg,...) av_printf_format(2
Log a generic warning message about a missing feature.
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
#define CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:684
const char data[16]
Definition: mxf.c:70
uint8_t * data
Definition: avcodec.h:973
CGA/EGA/VGA ROM data.
GetByteContext g
Definition: pictordec.c:36
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:123
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:161
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:145
static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:151
void av_log(void *avcl, int level, const char *fmt,...)
Definition: log.c:169
const char * name
Name of the codec implementation.
Definition: avcodec.h:2819
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:196
#define FFMIN(a, b)
Definition: common.h:57
int width
picture width / height.
Definition: avcodec.h:1229
if(ac->has_optimized_func)
#define AVERROR_PATCHWELCOME
Not yet implemented in Libav, patches welcome.
Definition: error.h:57
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:185
Libavcodec 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]
For video, size in bytes of each picture line.
Definition: frame.h:153
main external API structure.
Definition: avcodec.h:1050
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: utils.c:621
AVCodec ff_pictor_decoder
Definition: pictordec.c:245
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:330
int height
Definition: pictordec.c:34
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: frame.h:141
common internal api header.
void * priv_data
Definition: avcodec.h:1092
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:205
int nb_planes
Definition: pictordec.c:35
This structure stores compressed data.
Definition: avcodec.h:950