FFmpeg
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 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  * Pictor/PC Paint decoder
25  */
26 
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, unsigned 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  unsigned mask = ((1U << bits_per_plane) - 1) << shift;
66  int xl = *x;
67  int yl = *y;
68  int planel = *plane;
69  int pixels_per_value = 8/bits_per_plane;
70  value <<= shift;
71 
72  d = frame->data[0] + yl * frame->linesize[0];
73  while (run > 0) {
74  int j;
75  for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
76  d[xl] |= (value >> j) & mask;
77  xl += 1;
78  while (xl == s->width) {
79  yl -= 1;
80  xl = 0;
81  if (yl < 0) {
82  yl = s->height - 1;
83  planel += 1;
84  if (planel >= s->nb_planes)
85  goto end;
86  value <<= bits_per_plane;
87  mask <<= bits_per_plane;
88  }
89  d = frame->data[0] + yl * frame->linesize[0];
90  if (s->nb_planes == 1 &&
91  run*pixels_per_value >= s->width &&
92  pixels_per_value < (s->width / pixels_per_value * pixels_per_value)
93  ) {
94  for (; xl < pixels_per_value; xl ++) {
95  j = (j < bits_per_plane ? 8 : j) - bits_per_plane;
96  d[xl] |= (value >> j) & mask;
97  }
98  av_memcpy_backptr(d+xl, pixels_per_value, s->width - xl);
99  run -= s->width / pixels_per_value;
100  xl = s->width / pixels_per_value * pixels_per_value;
101  }
102  }
103  }
104  run--;
105  }
106 end:
107  *x = xl;
108  *y = yl;
109  *plane = planel;
110 }
111 
112 static const uint8_t cga_mode45_index[6][4] = {
113  [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity
114  [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity
115  [2] = { 0, 3, 4, 7 }, // mode5, low intensity
116  [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity
117  [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity
118  [5] = { 0, 11, 12, 15 }, // mode5, high intensity
119 };
120 
121 static int decode_frame(AVCodecContext *avctx,
122  void *data, int *got_frame,
123  AVPacket *avpkt)
124 {
125  PicContext *s = avctx->priv_data;
126  AVFrame *frame = data;
127  uint32_t *palette;
128  int bits_per_plane, bpp, etype, esize, npal, pos_after_pal;
129  int i, x, y, plane, tmp, ret, val;
130 
131  bytestream2_init(&s->g, avpkt->data, avpkt->size);
132 
133  if (bytestream2_get_bytes_left(&s->g) < 11)
134  return AVERROR_INVALIDDATA;
135 
136  if (bytestream2_get_le16u(&s->g) != 0x1234)
137  return AVERROR_INVALIDDATA;
138 
139  s->width = bytestream2_get_le16u(&s->g);
140  s->height = bytestream2_get_le16u(&s->g);
141  bytestream2_skip(&s->g, 4);
142  tmp = bytestream2_get_byteu(&s->g);
143  bits_per_plane = tmp & 0xF;
144  s->nb_planes = (tmp >> 4) + 1;
145  bpp = bits_per_plane * s->nb_planes;
146  if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
147  avpriv_request_sample(avctx, "Unsupported bit depth");
148  return AVERROR_PATCHWELCOME;
149  }
150 
151  if (bytestream2_peek_byte(&s->g) == 0xFF || bpp == 1 || bpp == 4 || bpp == 8) {
152  bytestream2_skip(&s->g, 2);
153  etype = bytestream2_get_le16(&s->g);
154  esize = bytestream2_get_le16(&s->g);
155  if (bytestream2_get_bytes_left(&s->g) < esize)
156  return AVERROR_INVALIDDATA;
157  } else {
158  etype = -1;
159  esize = 0;
160  }
161 
162  avctx->pix_fmt = AV_PIX_FMT_PAL8;
163 
164  if (av_image_check_size(s->width, s->height, 0, avctx) < 0)
165  return -1;
166  if (s->width != avctx->width || s->height != avctx->height) {
167  ret = ff_set_dimensions(avctx, s->width, s->height);
168  if (ret < 0)
169  return ret;
170  }
171 
172  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
173  return ret;
174  memset(frame->data[0], 0, s->height * frame->linesize[0]);
175  frame->pict_type = AV_PICTURE_TYPE_I;
176  frame->palette_has_changed = 1;
177 
178  pos_after_pal = bytestream2_tell(&s->g) + esize;
179  palette = (uint32_t*)frame->data[1];
180  if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) {
181  int idx = bytestream2_get_byte(&s->g);
182  npal = 4;
183  for (i = 0; i < npal; i++)
184  palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
185  } else if (etype == 2) {
186  npal = FFMIN(esize, 16);
187  for (i = 0; i < npal; i++) {
188  int pal_idx = bytestream2_get_byte(&s->g);
189  palette[i] = ff_cga_palette[FFMIN(pal_idx, 15)];
190  }
191  } else if (etype == 3) {
192  npal = FFMIN(esize, 16);
193  for (i = 0; i < npal; i++) {
194  int pal_idx = bytestream2_get_byte(&s->g);
195  palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)];
196  }
197  } else if (etype == 4 || etype == 5) {
198  npal = FFMIN(esize / 3, 256);
199  for (i = 0; i < npal; i++) {
200  palette[i] = bytestream2_get_be24(&s->g) << 2;
201  palette[i] |= 0xFFU << 24 | palette[i] >> 6 & 0x30303;
202  }
203  } else {
204  if (bpp == 1) {
205  npal = 2;
206  palette[0] = 0xFF000000;
207  palette[1] = 0xFFFFFFFF;
208  } else if (bpp == 2) {
209  npal = 4;
210  for (i = 0; i < npal; i++)
211  palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
212  } else {
213  npal = 16;
214  memcpy(palette, ff_cga_palette, npal * 4);
215  }
216  }
217  // fill remaining palette entries
218  memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
219  // skip remaining palette bytes
220  bytestream2_seek(&s->g, pos_after_pal, SEEK_SET);
221 
222  val = 0;
223  y = s->height - 1;
224  if (bytestream2_get_le16(&s->g)) {
225  x = 0;
226  plane = 0;
227  while (bytestream2_get_bytes_left(&s->g) >= 6) {
228  int stop_size, marker, t1, t2;
229 
231  t2 = bytestream2_get_le16(&s->g);
232  stop_size = t1 - FFMIN(t1, t2);
233  // ignore uncompressed block size
234  bytestream2_skip(&s->g, 2);
235  marker = bytestream2_get_byte(&s->g);
236 
237  while (plane < s->nb_planes &&
238  bytestream2_get_bytes_left(&s->g) > stop_size) {
239  int run = 1;
240  val = bytestream2_get_byte(&s->g);
241  if (val == marker) {
242  run = bytestream2_get_byte(&s->g);
243  if (run == 0)
244  run = bytestream2_get_le16(&s->g);
245  val = bytestream2_get_byte(&s->g);
246  }
247  if (!bytestream2_get_bytes_left(&s->g))
248  break;
249 
250  if (bits_per_plane == 8) {
251  picmemset_8bpp(s, frame, val, run, &x, &y);
252  if (y < 0)
253  goto finish;
254  } else {
255  picmemset(s, frame, val, run, &x, &y, &plane, bits_per_plane);
256  }
257  }
258  }
259 
260  if (s->nb_planes - plane > 1)
261  return AVERROR_INVALIDDATA;
262 
263  if (plane < s->nb_planes && x < avctx->width) {
264  int run = (y + 1) * avctx->width - x;
265  if (bits_per_plane == 8)
266  picmemset_8bpp(s, frame, val, run, &x, &y);
267  else
268  picmemset(s, frame, val, run / (8 / bits_per_plane), &x, &y, &plane, bits_per_plane);
269  }
270  } else {
271  while (y >= 0 && bytestream2_get_bytes_left(&s->g) > 0) {
272  memcpy(frame->data[0] + y * frame->linesize[0], s->g.buffer, FFMIN(avctx->width, bytestream2_get_bytes_left(&s->g)));
273  bytestream2_skip(&s->g, avctx->width);
274  y--;
275  }
276  }
277 finish:
278 
279  *got_frame = 1;
280  return avpkt->size;
281 }
282 
284  .name = "pictor",
285  .long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
286  .type = AVMEDIA_TYPE_VIDEO,
287  .id = AV_CODEC_ID_PICTOR,
288  .priv_data_size = sizeof(PicContext),
289  .decode = decode_frame,
290  .capabilities = AV_CODEC_CAP_DR1,
291 };
picmemset
static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run, int *x, int *y, int *plane, int bits_per_plane)
Definition: pictordec.c:60
AVCodec
AVCodec.
Definition: codec.h:202
cga_mode45_index
static const uint8_t cga_mode45_index[6][4]
Definition: pictordec.c:112
ff_cga_palette
const uint32_t ff_cga_palette[16]
Definition: cga_data.c:30
GetByteContext
Definition: bytestream.h:33
decode_frame
static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame, AVPacket *avpkt)
Definition: pictordec.c:121
bytestream2_seek
static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence)
Definition: bytestream.h:212
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:26
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:373
data
const char data[16]
Definition: mxf.c:143
t1
#define t1
Definition: regdef.h:29
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
finish
static void finish(void)
Definition: movenc.c:342
PicContext::height
int height
Definition: pictordec.c:34
U
#define U(x)
Definition: vp56_arith.h:37
PicContext
Definition: pictordec.c:33
val
static double val(void *priv, double ch)
Definition: aeval.c:76
PicContext::width
int width
Definition: pictordec.c:34
mask
static const uint16_t mask[17]
Definition: lzw.c:38
av_memcpy_backptr
void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
Overlapping memcpy() implementation.
Definition: mem.c:454
decode
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
width
#define width
s
#define s(width, name)
Definition: cbs_vp9.c:257
if
if(ret)
Definition: filter_design.txt:179
PicContext::nb_planes
int nb_planes
Definition: pictordec.c:35
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
run
uint8_t run
Definition: svq3.c:203
ff_ega_palette
const uint32_t ff_ega_palette[64]
Definition: cga_data.c:35
AV_CODEC_ID_PICTOR
@ AV_CODEC_ID_PICTOR
Definition: codec_id.h:191
AVPALETTE_SIZE
#define AVPALETTE_SIZE
Definition: pixfmt.h:32
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
picmemset_8bpp
static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run, int *x, int *y)
Definition: pictordec.c:39
bytestream2_get_bytes_left
static av_always_inline int bytestream2_get_bytes_left(GetByteContext *g)
Definition: bytestream.h:158
bytestream2_tell
static av_always_inline int bytestream2_tell(GetByteContext *g)
Definition: bytestream.h:192
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1652
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:374
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
ff_pictor_decoder
const AVCodec ff_pictor_decoder
Definition: pictordec.c:283
cga_data.h
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:271
value
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default value
Definition: writing_filters.txt:86
FFMIN
#define FFMIN(a, b)
Definition: macros.h:49
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:209
AVCodecContext::height
int height
Definition: avcodec.h:556
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:593
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVCodecContext
main external API structure.
Definition: avcodec.h:383
t2
#define t2
Definition: regdef.h:30
PicContext::g
GetByteContext g
Definition: pictordec.c:36
shift
static int shift(int a, int b)
Definition: sonic.c:83
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
ff_set_dimensions
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:86
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:37
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:410
AVPacket
This structure stores compressed data.
Definition: packet.h:350
d
d
Definition: ffmpeg_filter.c:156
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:556
bytestream.h
imgutils.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
av_image_check_size
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:318