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 "codec_internal.h"
32 #include "internal.h"
33 
34 typedef struct PicContext {
35  int width, height;
36  int nb_planes;
38 } PicContext;
39 
40 static void picmemset_8bpp(PicContext *s, AVFrame *frame, int value, int run,
41  int *x, int *y)
42 {
43  while (run > 0) {
44  uint8_t *d = frame->data[0] + *y * frame->linesize[0];
45  if (*x + run >= s->width) {
46  int n = s->width - *x;
47  memset(d + *x, value, n);
48  run -= n;
49  *x = 0;
50  *y -= 1;
51  if (*y < 0)
52  break;
53  } else {
54  memset(d + *x, value, run);
55  *x += run;
56  break;
57  }
58  }
59 }
60 
61 static void picmemset(PicContext *s, AVFrame *frame, unsigned value, int run,
62  int *x, int *y, int *plane, int bits_per_plane)
63 {
64  uint8_t *d;
65  int shift = *plane * bits_per_plane;
66  unsigned mask = ((1U << bits_per_plane) - 1) << shift;
67  int xl = *x;
68  int yl = *y;
69  int planel = *plane;
70  int pixels_per_value = 8/bits_per_plane;
71  value <<= shift;
72 
73  d = frame->data[0] + yl * frame->linesize[0];
74  while (run > 0) {
75  int j;
76  for (j = 8-bits_per_plane; j >= 0; j -= bits_per_plane) {
77  d[xl] |= (value >> j) & mask;
78  xl += 1;
79  while (xl == s->width) {
80  yl -= 1;
81  xl = 0;
82  if (yl < 0) {
83  yl = s->height - 1;
84  planel += 1;
85  if (planel >= s->nb_planes)
86  goto end;
87  value <<= bits_per_plane;
88  mask <<= bits_per_plane;
89  }
90  d = frame->data[0] + yl * frame->linesize[0];
91  if (s->nb_planes == 1 &&
92  run*pixels_per_value >= s->width &&
93  pixels_per_value < (s->width / pixels_per_value * pixels_per_value)
94  ) {
95  for (; xl < pixels_per_value; xl ++) {
96  j = (j < bits_per_plane ? 8 : j) - bits_per_plane;
97  d[xl] |= (value >> j) & mask;
98  }
99  av_memcpy_backptr(d+xl, pixels_per_value, s->width - xl);
100  run -= s->width / pixels_per_value;
101  xl = s->width / pixels_per_value * pixels_per_value;
102  }
103  }
104  }
105  run--;
106  }
107 end:
108  *x = xl;
109  *y = yl;
110  *plane = planel;
111 }
112 
113 static const uint8_t cga_mode45_index[6][4] = {
114  [0] = { 0, 3, 5, 7 }, // mode4, palette#1, low intensity
115  [1] = { 0, 2, 4, 6 }, // mode4, palette#2, low intensity
116  [2] = { 0, 3, 4, 7 }, // mode5, low intensity
117  [3] = { 0, 11, 13, 15 }, // mode4, palette#1, high intensity
118  [4] = { 0, 10, 12, 14 }, // mode4, palette#2, high intensity
119  [5] = { 0, 11, 12, 15 }, // mode5, high intensity
120 };
121 
123  int *got_frame, AVPacket *avpkt)
124 {
125  PicContext *s = avctx->priv_data;
126  uint32_t *palette;
127  int bits_per_plane, bpp, etype, esize, npal, pos_after_pal;
128  int i, x, y, plane, tmp, ret, val;
129 
130  bytestream2_init(&s->g, avpkt->data, avpkt->size);
131 
132  if (bytestream2_get_bytes_left(&s->g) < 11)
133  return AVERROR_INVALIDDATA;
134 
135  if (bytestream2_get_le16u(&s->g) != 0x1234)
136  return AVERROR_INVALIDDATA;
137 
138  s->width = bytestream2_get_le16u(&s->g);
139  s->height = bytestream2_get_le16u(&s->g);
140  bytestream2_skip(&s->g, 4);
141  tmp = bytestream2_get_byteu(&s->g);
142  bits_per_plane = tmp & 0xF;
143  s->nb_planes = (tmp >> 4) + 1;
144  bpp = bits_per_plane * s->nb_planes;
145  if (bits_per_plane > 8 || bpp < 1 || bpp > 32) {
146  avpriv_request_sample(avctx, "Unsupported bit depth");
147  return AVERROR_PATCHWELCOME;
148  }
149 
150  if (bytestream2_peek_byte(&s->g) == 0xFF || bpp == 1 || bpp == 4 || bpp == 8) {
151  bytestream2_skip(&s->g, 2);
152  etype = bytestream2_get_le16(&s->g);
153  esize = bytestream2_get_le16(&s->g);
154  if (bytestream2_get_bytes_left(&s->g) < esize)
155  return AVERROR_INVALIDDATA;
156  } else {
157  etype = -1;
158  esize = 0;
159  }
160 
161  avctx->pix_fmt = AV_PIX_FMT_PAL8;
162 
163  if (av_image_check_size(s->width, s->height, 0, avctx) < 0)
164  return -1;
165  if (s->width != avctx->width || s->height != avctx->height) {
166  ret = ff_set_dimensions(avctx, s->width, s->height);
167  if (ret < 0)
168  return ret;
169  }
170 
171  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
172  return ret;
173  memset(frame->data[0], 0, s->height * frame->linesize[0]);
174  frame->pict_type = AV_PICTURE_TYPE_I;
175  frame->palette_has_changed = 1;
176 
177  pos_after_pal = bytestream2_tell(&s->g) + esize;
178  palette = (uint32_t*)frame->data[1];
179  if (etype == 1 && esize > 1 && bytestream2_peek_byte(&s->g) < 6) {
180  int idx = bytestream2_get_byte(&s->g);
181  npal = 4;
182  for (i = 0; i < npal; i++)
183  palette[i] = ff_cga_palette[ cga_mode45_index[idx][i] ];
184  } else if (etype == 2) {
185  npal = FFMIN(esize, 16);
186  for (i = 0; i < npal; i++) {
187  int pal_idx = bytestream2_get_byte(&s->g);
188  palette[i] = ff_cga_palette[FFMIN(pal_idx, 15)];
189  }
190  } else if (etype == 3) {
191  npal = FFMIN(esize, 16);
192  for (i = 0; i < npal; i++) {
193  int pal_idx = bytestream2_get_byte(&s->g);
194  palette[i] = ff_ega_palette[FFMIN(pal_idx, 63)];
195  }
196  } else if (etype == 4 || etype == 5) {
197  npal = FFMIN(esize / 3, 256);
198  for (i = 0; i < npal; i++) {
199  palette[i] = bytestream2_get_be24(&s->g) << 2;
200  palette[i] |= 0xFFU << 24 | palette[i] >> 6 & 0x30303;
201  }
202  } else {
203  if (bpp == 1) {
204  npal = 2;
205  palette[0] = 0xFF000000;
206  palette[1] = 0xFFFFFFFF;
207  } else if (bpp == 2) {
208  npal = 4;
209  for (i = 0; i < npal; i++)
210  palette[i] = ff_cga_palette[ cga_mode45_index[0][i] ];
211  } else {
212  npal = 16;
213  memcpy(palette, ff_cga_palette, npal * 4);
214  }
215  }
216  // fill remaining palette entries
217  memset(palette + npal, 0, AVPALETTE_SIZE - npal * 4);
218  // skip remaining palette bytes
219  bytestream2_seek(&s->g, pos_after_pal, SEEK_SET);
220 
221  val = 0;
222  y = s->height - 1;
223  if (bytestream2_get_le16(&s->g)) {
224  x = 0;
225  plane = 0;
226  while (bytestream2_get_bytes_left(&s->g) >= 6) {
227  int stop_size, marker, t1, t2;
228 
230  t2 = bytestream2_get_le16(&s->g);
231  stop_size = t1 - FFMIN(t1, t2);
232  // ignore uncompressed block size
233  bytestream2_skip(&s->g, 2);
234  marker = bytestream2_get_byte(&s->g);
235 
236  while (plane < s->nb_planes &&
237  bytestream2_get_bytes_left(&s->g) > stop_size) {
238  int run = 1;
239  val = bytestream2_get_byte(&s->g);
240  if (val == marker) {
241  run = bytestream2_get_byte(&s->g);
242  if (run == 0)
243  run = bytestream2_get_le16(&s->g);
244  val = bytestream2_get_byte(&s->g);
245  }
246  if (!bytestream2_get_bytes_left(&s->g))
247  break;
248 
249  if (bits_per_plane == 8) {
250  picmemset_8bpp(s, frame, val, run, &x, &y);
251  if (y < 0)
252  goto finish;
253  } else {
254  picmemset(s, frame, val, run, &x, &y, &plane, bits_per_plane);
255  }
256  }
257  }
258 
259  if (s->nb_planes - plane > 1)
260  return AVERROR_INVALIDDATA;
261 
262  if (plane < s->nb_planes && x < avctx->width) {
263  int run = (y + 1) * avctx->width - x;
264  if (bits_per_plane == 8)
265  picmemset_8bpp(s, frame, val, run, &x, &y);
266  else
267  picmemset(s, frame, val, run / (8 / bits_per_plane), &x, &y, &plane, bits_per_plane);
268  }
269  } else {
270  while (y >= 0 && bytestream2_get_bytes_left(&s->g) > 0) {
271  memcpy(frame->data[0] + y * frame->linesize[0], s->g.buffer, FFMIN(avctx->width, bytestream2_get_bytes_left(&s->g)));
272  bytestream2_skip(&s->g, avctx->width);
273  y--;
274  }
275  }
276 finish:
277 
278  *got_frame = 1;
279  return avpkt->size;
280 }
281 
283  .p.name = "pictor",
284  .p.long_name = NULL_IF_CONFIG_SMALL("Pictor/PC Paint"),
285  .p.type = AVMEDIA_TYPE_VIDEO,
286  .p.id = AV_CODEC_ID_PICTOR,
287  .p.capabilities = AV_CODEC_CAP_DR1,
288  .priv_data_size = sizeof(PicContext),
290 };
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:61
cga_mode45_index
static const uint8_t cga_mode45_index[6][4]
Definition: pictordec.c:113
ff_cga_palette
const uint32_t ff_cga_palette[16]
Definition: cga_data.c:30
GetByteContext
Definition: bytestream.h:33
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:325
tmp
static uint8_t tmp[11]
Definition: aes_ctr.c:28
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:374
FFCodec
Definition: codec_internal.h:112
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
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:116
finish
static void finish(void)
Definition: movenc.c:342
PicContext::height
int height
Definition: pictordec.c:35
U
#define U(x)
Definition: vp56_arith.h:37
PicContext
Definition: pictordec.c:34
val
static double val(void *priv, double ch)
Definition: aeval.c:77
PicContext::width
int width
Definition: pictordec.c:35
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:455
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:254
s
#define s(width, name)
Definition: cbs_vp9.c:256
if
if(ret)
Definition: filter_design.txt:179
PicContext::nb_planes
int nb_planes
Definition: pictordec.c:36
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
run
uint8_t run
Definition: svq3.c:205
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:40
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:1403
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:375
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
codec_internal.h
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:203
AVCodecContext::height
int height
Definition: avcodec.h:562
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:599
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:389
t2
#define t2
Definition: regdef.h:30
PicContext::g
GetByteContext g
Definition: pictordec.c:37
shift
static int shift(int a, int b)
Definition: sonic.c:88
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:90
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:416
AVPacket
This structure stores compressed data.
Definition: packet.h:351
d
d
Definition: ffmpeg_filter.c:153
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:562
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
ff_pictor_decoder
const FFCodec ff_pictor_decoder
Definition: pictordec.c:282
decode_frame
static int decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt)
Definition: pictordec.c:122