FFmpeg
gemdec.c
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1 /*
2  * GEM Raster image decoder
3  * Copyright (c) 2021 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  * GEM Raster image decoder
25  */
26 
27 #include "avcodec.h"
28 #include "bytestream.h"
29 #include "codec_internal.h"
30 #include "decode.h"
31 
32 static const uint32_t gem_color_palette[16]={
33  0xFFFFFFFF, 0xFFFF0000, 0xFF00FF00, 0xFFFFFF00,
34  0xFF0000FF, 0xFFFF00FF, 0xFF00FFFF, 0xFFAEAEAE,
35  0xFF555555, 0xFFAE0000, 0xFF00AE00, 0xFFAEAE00,
36  0xFF0000AE, 0xFFAE00AE, 0xFF00AEAE, 0xFF000000,
37 };
38 
39 static const uint8_t gem_gray[256]={
40  0xFF, 0x7F, 0xBF, 0x3F, 0xDF, 0x5F, 0x9F, 0x1F, 0xEF, 0x6F, 0xAF, 0x2F, 0xCF, 0x4F, 0x8F, 0x0F,
41  0xF7, 0x77, 0xB7, 0x37, 0xD7, 0x57, 0x97, 0x17, 0xE7, 0x67, 0xA7, 0x27, 0xC7, 0x47, 0x87, 0x07,
42  0xFB, 0x7B, 0xBB, 0x3B, 0xDB, 0x5B, 0x9B, 0x1B, 0xEB, 0x6B, 0xAB, 0x2B, 0xCB, 0x4B, 0x8B, 0x0B,
43  0xF3, 0x73, 0xB3, 0x33, 0xD3, 0x53, 0x93, 0x13, 0xE3, 0x63, 0xA3, 0x23, 0xC3, 0x43, 0x83, 0x03,
44  0xFD, 0x7D, 0xBD, 0x3D, 0xDD, 0x5D, 0x9D, 0x1D, 0xED, 0x6D, 0xAD, 0x2D, 0xCD, 0x4D, 0x8D, 0x0D,
45  0xF5, 0x75, 0xB5, 0x35, 0xD5, 0x55, 0x95, 0x15, 0xE5, 0x65, 0xA5, 0x25, 0xC5, 0x45, 0x85, 0x05,
46  0xF9, 0x79, 0xB9, 0x39, 0xD9, 0x59, 0x99, 0x19, 0xE9, 0x69, 0xA9, 0x29, 0xC9, 0x49, 0x89, 0x09,
47  0xF1, 0x71, 0xB1, 0x31, 0xD1, 0x51, 0x91, 0x11, 0xE1, 0x61, 0xA1, 0x21, 0xC1, 0x41, 0x81, 0x01,
48  0xFE, 0x7E, 0xBE, 0x3E, 0xDE, 0x5E, 0x9E, 0x1E, 0xEE, 0x6E, 0xAE, 0x2E, 0xCE, 0x4E, 0x8E, 0x0E,
49  0xF6, 0x76, 0xB6, 0x36, 0xD6, 0x56, 0x96, 0x16, 0xE6, 0x66, 0xA6, 0x26, 0xC6, 0x46, 0x86, 0x06,
50  0xFA, 0x7A, 0xBA, 0x3A, 0xDA, 0x5A, 0x9A, 0x1A, 0xEA, 0x6A, 0xAA, 0x2A, 0xCA, 0x4A, 0x8A, 0x0A,
51  0xF2, 0x72, 0xB2, 0x32, 0xD2, 0x52, 0x92, 0x12, 0xE2, 0x62, 0xA2, 0x22, 0xC2, 0x42, 0x82, 0x02,
52  0xFC, 0x7C, 0xBC, 0x3C, 0xDC, 0x5C, 0x9C, 0x1C, 0xEC, 0x6C, 0xAC, 0x2C, 0xCC, 0x4C, 0x8C, 0x0C,
53  0xF4, 0x74, 0xB4, 0x34, 0xD4, 0x54, 0x94, 0x14, 0xE4, 0x64, 0xA4, 0x24, 0xC4, 0x44, 0x84, 0x04,
54  0xF8, 0x78, 0xB8, 0x38, 0xD8, 0x58, 0x98, 0x18, 0xE8, 0x68, 0xA8, 0x28, 0xC8, 0x48, 0x88, 0x08,
55  0xF0, 0x70, 0xB0, 0x30, 0xD0, 0x50, 0x90, 0x10, 0xE0, 0x60, 0xA0, 0x20, 0xC0, 0x40, 0x80, 0x00,
56 };
57 
58 typedef struct {
59  int y, pl, x, vdup;
60 } State;
61 
62 static void put_lines_bits(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p)
63 {
64  int pl_byte = state->pl / 8;
65  int pl_bit = state->pl & 7;
66  for (int y = 0; y < state->vdup && (state->y + y) < avctx->height; y++)
67  for (int x = 0; x < row_width; x++)
68  for (int i = 7; i >= 0 && x * 8 + 7 - i < avctx->width; i--)
69  p->data[0][ (state->y + y) * p->linesize[0] + (x * 8 + 7 - i) * pixel_size + pl_byte] |= !!(row[x] & (1 << i)) << pl_bit;
70 
71  state->pl++;
72  if (state->pl >= planes) {
73  state->pl = 0;
74  state->y += state->vdup;
75  state->vdup = 1;
76  }
77 }
78 
79 static void put_lines_bytes(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p)
80 {
81  for (int y = 0; y < state->vdup && (state->y + y) < avctx->height; y++)
82  memcpy(p->data[0] + (state->y + y) * p->linesize[0], row, avctx->width * pixel_size);
83 
84  state->y += state->vdup;
85  state->vdup = 1;
86 }
87 
88 static int gem_decode_frame(AVCodecContext *avctx, AVFrame *p,
89  int *got_frame, AVPacket *avpkt)
90 {
91  const uint8_t *buf = avpkt->data;
92  int buf_size = avpkt->size;
93  const uint8_t *buf_end = buf + buf_size;
94  int header_size, planes, pattern_size, tag = 0, count_scalar = 1, ret;
95  unsigned int x, count, v;
96  GetByteContext gb;
97  uint32_t *palette;
98  const uint8_t * b;
99  uint8_t * row;
100  int row_width, pixel_size;
101  State state = {.y = 0, .pl = 0, .x = 0, .vdup = 1};
102  void (*put_lines)(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p);
103  int width, height;
104 
105  if (buf_size <= 16)
106  return AVERROR_INVALIDDATA;
107 
108  bytestream2_init(&gb, buf + 2, buf_size - 2);
109  header_size = bytestream2_get_be16(&gb);
110  if (header_size < 8 || buf_size <= header_size * 2)
111  return AVERROR_INVALIDDATA;
112 
113  planes = bytestream2_get_be16(&gb);
114  pattern_size = bytestream2_get_be16(&gb);
115  avctx->sample_aspect_ratio.num = bytestream2_get_be16(&gb);
116  avctx->sample_aspect_ratio.den = bytestream2_get_be16(&gb);
117  width = bytestream2_get_be16(&gb);
118  height = bytestream2_get_be16(&gb);
119  ret = ff_set_dimensions(avctx, width, height);
120  if (ret < 0)
121  return ret;
122 
123  row_width = (avctx->width + 7) / 8;
124  put_lines = put_lines_bits;
125 
126  if (header_size == 9) {
127  count_scalar = bytestream2_get_be16(&gb);
128  if (count_scalar != 3) {
129  avpriv_request_sample(avctx, "count_scalar=%d", count_scalar);
130  return AVERROR_PATCHWELCOME;
131  }
132  planes = 24;
133  avctx->pix_fmt = AV_PIX_FMT_BGR24;
134  pixel_size = 3;
135  } else if (planes == 15) {
136 #if HAVE_BIGENDIAN
137  avctx->pix_fmt = AV_PIX_FMT_BGR555BE;
138 #else
139  avctx->pix_fmt = AV_PIX_FMT_BGR555LE;
140 #endif
141  pixel_size = 2;
142  } else if (planes == 16) {
143  avctx->pix_fmt = AV_PIX_FMT_RGB565BE;
144  pixel_size = 2;
145  } else if (planes == 24) {
146  avctx->pix_fmt = AV_PIX_FMT_RGB24;
147  pixel_size = 3;
148  } else if (planes == 32) {
149  avctx->pix_fmt = AV_PIX_FMT_0RGB;
150  pixel_size = 4;
151  } else {
152  avctx->pix_fmt = AV_PIX_FMT_PAL8;
153  pixel_size = 1;
154  }
155 
156  if (header_size >= 11)
157  tag = bytestream2_peek_be32(&gb);
158 
159  if (tag == AV_RB32("STTT")) {
160  if (planes != 4) {
161  avpriv_request_sample(avctx, "STTT planes=%d", planes);
162  return AVERROR_PATCHWELCOME;
163  }
164  } else if (tag == AV_RB32("TIMG")) {
165  if (planes != 15) {
166  avpriv_request_sample(avctx, "TIMG planes=%d", planes);
167  return AVERROR_PATCHWELCOME;
168  }
169  } else if (tag == AV_RB32("XIMG")) {
170  if (planes != 1 && planes != 2 && planes != 4 && planes != 8 && planes != 16 && planes != 24 && planes != 32) {
171  avpriv_request_sample(avctx, "XIMG planes=%d", planes);
172  return AVERROR_PATCHWELCOME;
173  }
174  } else if (planes != 1 && planes != 2 && planes != 3 && planes != 4 && planes != 8 && planes != 16 && planes != 24) {
175  avpriv_request_sample(avctx, "planes=%d", planes);
176  return AVERROR_PATCHWELCOME;
177  }
178 
179  if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
180  return ret;
181 
183  p->key_frame = 1;
184  p->palette_has_changed = 1;
185  palette = (uint32_t *)p->data[1];
186 
187  if (tag == AV_RB32("STTT")) {
188  bytestream2_skip(&gb, 6);
189  if (planes == 4) {
190  for (int i = 0; i < (1 << planes); i++) {
191  int v = bytestream2_get_be16(&gb);
192  int r = ((v >> 8) & 0x7) << 5;
193  int g = ((v >> 4) & 0x7) << 5;
194  int b = ((v ) & 0x7) << 5;
195  palette[i] = 0xFF000000 | r << 16 | g << 8 | b;
196  }
197  } else {
198  av_assert0(0);
199  }
200  } else if (tag == AV_RB32("TIMG")) {
201  bytestream2_skip(&gb, 4);
202  if (planes != 15) {
203  av_assert0(0);
204  }
205  } else if (tag == AV_RB32("XIMG")) {
206  bytestream2_skip(&gb, 6);
207  if (planes == 1 || planes == 2 || planes == 4 || planes == 8) {
208  for (int i = 0; i < (1 << planes); i++) {
209  int r = (bytestream2_get_be16(&gb) * 51 + 100) / 200;
210  int g = (bytestream2_get_be16(&gb) * 51 + 100) / 200;
211  int b = (bytestream2_get_be16(&gb) * 51 + 100) / 200;
212  palette[i] = 0xFF000000 | r << 16 | g << 8 | b;
213  }
214  } else if (planes == 16) {
215  planes = 1;
216  row_width = ((avctx->width + 7)/8)*8 * pixel_size;
217  put_lines = put_lines_bytes;
218  } else if (planes == 24) {
219  planes = 1;
220  row_width = ((avctx->width + 15)/16)*16 * pixel_size;
221  put_lines = put_lines_bytes;
222  } else if (planes == 32) {
223  planes = 1;
224  row_width = avctx->width * pixel_size;
225  put_lines = put_lines_bytes;
226  } else {
227  av_assert0(0);
228  }
229  } else if (planes == 1) {
230  palette[0] = 0xFFFFFFFF;
231  palette[1] = 0xFF000000;
232  } else if (planes == 2 || planes == 3 || planes == 4) {
233  if (header_size == 9 + (1 << planes)) {
234  bytestream2_skip(&gb, 2);
235  for (int i = 0; i < (1 << planes); i++) {
236  int v = bytestream2_get_be16(&gb);
237  int r = ((v >> 8) & 0x7) << 5;
238  int g = ((v >> 4) & 0x7) << 5;
239  int b = ((v ) & 0x7) << 5;
240  palette[i] = 0xFF000000 | r << 16 | g << 8 | b;
241  }
242  } else
243  memcpy(palette, gem_color_palette, sizeof(gem_color_palette));
244  } else if (planes == 8) {
245  for (int i = 0; i < 256; i++)
246  palette[i] = 0xFF000000 | (gem_gray[i]<<16) | (gem_gray[i]<<8) | gem_gray[i];
247  } else if (planes == 16) {
248  planes = 1;
249  row_width = avctx->width * pixel_size;
250  put_lines = put_lines_bytes;
251  } else if (planes == 24) {
252  planes = 1;
253  row_width = avctx->width * pixel_size;
254  put_lines = put_lines_bytes;
255  } else
256  av_assert0(0);
257 
258  ret = av_reallocp_array(&avctx->priv_data, planes, row_width);
259  if (ret < 0)
260  return ret;
261  row = avctx->priv_data;
262 
263  memset(p->data[0], 0, avctx->height * p->linesize[0]);
264  b = buf + header_size * 2;
265  x = 0;
266 
267 #define SKIP \
268 do { \
269  x++; \
270  if (x >= row_width) { \
271  put_lines(avctx, planes, row_width, pixel_size, &state, row + state.pl * row_width, p); \
272  if (state.y >= avctx->height) goto abort; \
273  x = 0; \
274  } \
275 } while(0)
276 
277 #define PUT(v) \
278 do { \
279  row[state.pl * row_width + x++] = v; \
280  if (x >= row_width) { \
281  put_lines(avctx, planes, row_width, pixel_size, &state, row + state.pl * row_width, p); \
282  if (state.y >= avctx->height) goto abort; \
283  x = 0; \
284  } \
285 } while(0)
286 
287  while(b < buf_end) {
288  int opcode = *b++;
289  if (opcode == 0x80) { /* copy */
290  if (b >= buf_end)
291  goto abort;
292  count = *b++;
293  if (!count)
294  count = 256;
295  count *= count_scalar;
296  for (int j = 0; j < count; j++) {
297  if (b >= buf_end)
298  goto abort;
299  PUT(*b++);
300  }
301  } else if (opcode) { /* run */
302  count = opcode & 0x7f;
303  if (!count)
304  count = 256;
305  count *= count_scalar;
306  v = opcode & 0x80 ? 0xFF : 0x00;
307  for (int i = 0; i < count; i++)
308  PUT(v);
309  } else {
310  if (b >= buf_end)
311  goto abort;
312  count = *b++;
313  if (count) { /* pattern */
314  if (b > buf_end - pattern_size)
315  goto abort;
316 
317  count *= count_scalar;
318  for (int j = 0; j < count; j++)
319  for (int k = 0; k < pattern_size; k++)
320  PUT(b[k]);
321 
322  b += pattern_size;
323  } else {
324  if (b >= buf_end)
325  goto abort;
326  count = *b++;
327  if (count == 0xFF) { /* vertical duplication */
328  if (b >= buf_end)
329  goto abort;
330  state.vdup = *b++;
331  if (!state.vdup)
332  state.vdup = 256;
333  } else { /* horizontal duplication */
334  for (int i = 0; i < count + 1; i++)
335  SKIP;
336  }
337  }
338  }
339  }
340 
341 abort:
342 
343  *got_frame = 1;
344  return buf_size;
345 }
346 
347 static av_cold int gem_close(AVCodecContext *avctx)
348 {
349  av_freep(&avctx->priv_data);
350  return 0;
351 }
352 
354  .p.name = "gem",
355  CODEC_LONG_NAME("GEM Raster image"),
356  .p.type = AVMEDIA_TYPE_VIDEO,
357  .p.id = AV_CODEC_ID_GEM,
358  .p.capabilities = AV_CODEC_CAP_DR1,
360  .close = gem_close,
361 };
ff_gem_decoder
const FFCodec ff_gem_decoder
Definition: gemdec.c:353
r
const char * r
Definition: vf_curves.c:116
GetByteContext
Definition: bytestream.h:33
state
static struct @335 state
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:325
AVPacket::data
uint8_t * data
Definition: packet.h:374
b
#define b
Definition: input.c:41
FFCodec
Definition: codec_internal.h:119
AV_PIX_FMT_BGR24
@ AV_PIX_FMT_BGR24
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:69
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:91
AVFrame::data
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:346
bytestream2_skip
static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size)
Definition: bytestream.h:168
gem_gray
static const uint8_t gem_gray[256]
Definition: gemdec.c:39
PUT
#define PUT(v)
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:123
AVFrame::key_frame
int key_frame
1 -> keyframe, 0-> not
Definition: frame.h:417
AVRational::num
int num
Numerator.
Definition: rational.h:59
av_cold
#define av_cold
Definition: attributes.h:90
gem_color_palette
static const uint32_t gem_color_palette[16]
Definition: gemdec.c:32
width
#define width
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:279
put_lines_bits
static void put_lines_bits(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State *state, uint8_t *row, AVFrame *p)
Definition: gemdec.c:62
g
const char * g
Definition: vf_curves.c:117
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
decode.h
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:264
if
if(ret)
Definition: filter_design.txt:179
AVERROR_PATCHWELCOME
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition: error.h:64
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition: avutil.h:274
gem_decode_frame
static int gem_decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)
Definition: gemdec.c:88
planes
static const struct @336 planes[]
AV_PIX_FMT_BGR555BE
@ AV_PIX_FMT_BGR555BE
packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), big-endian , X=unused/undefined
Definition: pixfmt.h:112
State::y
int y
Definition: gemdec.c:59
AVFrame::pict_type
enum AVPictureType pict_type
Picture type of the frame.
Definition: frame.h:422
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1450
AV_PIX_FMT_RGB24
@ AV_PIX_FMT_RGB24
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:68
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
codec_internal.h
AV_RB32
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_WL16 uint64_t_TMPL AV_WB64 unsigned int_TMPL AV_RB32
Definition: bytestream.h:96
height
#define height
av_reallocp_array
int av_reallocp_array(void *ptr, size_t nmemb, size_t size)
Allocate, reallocate an array through a pointer to a pointer.
Definition: mem.c:233
put_lines_bytes
static void put_lines_bytes(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State *state, uint8_t *row, AVFrame *p)
Definition: gemdec.c:79
State
Definition: gemdec.c:58
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:211
AVCodecContext::height
int height
Definition: avcodec.h:571
AVCodecContext::pix_fmt
enum AVPixelFormat pix_fmt
Pixel format, see AV_PIX_FMT_xxx.
Definition: avcodec.h:608
avcodec.h
AV_PIX_FMT_PAL8
@ AV_PIX_FMT_PAL8
8 bits with AV_PIX_FMT_RGB32 palette
Definition: pixfmt.h:77
tag
uint32_t tag
Definition: movenc.c:1646
ret
ret
Definition: filter_design.txt:187
gem_close
static av_cold int gem_close(AVCodecContext *avctx)
Definition: gemdec.c:347
AVCodecContext
main external API structure.
Definition: avcodec.h:398
AVFrame::palette_has_changed
int palette_has_changed
Tell user application that palette has changed from previous frame.
Definition: frame.h:487
AVRational::den
int den
Denominator.
Definition: rational.h:60
AV_PIX_FMT_RGB565BE
@ AV_PIX_FMT_RGB565BE
packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), big-endian
Definition: pixfmt.h:105
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
SKIP
#define SKIP
AV_CODEC_ID_GEM
@ AV_CODEC_ID_GEM
Definition: codec_id.h:314
avpriv_request_sample
#define avpriv_request_sample(...)
Definition: tableprint_vlc.h:36
AV_PIX_FMT_BGR555LE
@ AV_PIX_FMT_BGR555LE
packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), little-endian, X=unused/undefined
Definition: pixfmt.h:113
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:425
AVPacket
This structure stores compressed data.
Definition: packet.h:351
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
AVCodecContext::width
int width
picture width / height.
Definition: avcodec.h:571
bytestream.h
bytestream2_init
static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)
Definition: bytestream.h:137
AVFrame::linesize
int linesize[AV_NUM_DATA_POINTERS]
For video, a positive or negative value, which is typically indicating the size in bytes of each pict...
Definition: frame.h:370
AV_PIX_FMT_0RGB
@ AV_PIX_FMT_0RGB
packed RGB 8:8:8, 32bpp, XRGBXRGB... X=unused/undefined
Definition: pixfmt.h:227
AVERROR_INVALIDDATA
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:61
AVCodecContext::sample_aspect_ratio
AVRational sample_aspect_ratio
sample aspect ratio (0 if unknown) That is the width of a pixel divided by the height of the pixel.
Definition: avcodec.h:768