FFmpeg: libavcodec/gemdec.c Source File

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libavcodec

gemdec.c

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1 /*

2 * GEM Raster image decoder

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 */

22 /**

23 * @file

24 * GEM Raster image decoder

25 */

27 #include "libavutil/mem.h"

28 #include "avcodec.h"

29 #include "bytestream.h"

30 #include "codec_internal.h"

31 #include "decode.h"

33 static const uint32_t gem_color_palette[16]={

34 0xFFFFFFFF, 0xFFFF0000, 0xFF00FF00, 0xFFFFFF00,

35 0xFF0000FF, 0xFFFF00FF, 0xFF00FFFF, 0xFFAEAEAE,

36 0xFF555555, 0xFFAE0000, 0xFF00AE00, 0xFFAEAE00,

37 0xFF0000AE, 0xFFAE00AE, 0xFF00AEAE, 0xFF000000,

38 };

40 static const uint8_t gem_gray[256]={

41 0xFF, 0x7F, 0xBF, 0x3F, 0xDF, 0x5F, 0x9F, 0x1F, 0xEF, 0x6F, 0xAF, 0x2F, 0xCF, 0x4F, 0x8F, 0x0F,

42 0xF7, 0x77, 0xB7, 0x37, 0xD7, 0x57, 0x97, 0x17, 0xE7, 0x67, 0xA7, 0x27, 0xC7, 0x47, 0x87, 0x07,

43 0xFB, 0x7B, 0xBB, 0x3B, 0xDB, 0x5B, 0x9B, 0x1B, 0xEB, 0x6B, 0xAB, 0x2B, 0xCB, 0x4B, 0x8B, 0x0B,

44 0xF3, 0x73, 0xB3, 0x33, 0xD3, 0x53, 0x93, 0x13, 0xE3, 0x63, 0xA3, 0x23, 0xC3, 0x43, 0x83, 0x03,

45 0xFD, 0x7D, 0xBD, 0x3D, 0xDD, 0x5D, 0x9D, 0x1D, 0xED, 0x6D, 0xAD, 0x2D, 0xCD, 0x4D, 0x8D, 0x0D,

46 0xF5, 0x75, 0xB5, 0x35, 0xD5, 0x55, 0x95, 0x15, 0xE5, 0x65, 0xA5, 0x25, 0xC5, 0x45, 0x85, 0x05,

47 0xF9, 0x79, 0xB9, 0x39, 0xD9, 0x59, 0x99, 0x19, 0xE9, 0x69, 0xA9, 0x29, 0xC9, 0x49, 0x89, 0x09,

48 0xF1, 0x71, 0xB1, 0x31, 0xD1, 0x51, 0x91, 0x11, 0xE1, 0x61, 0xA1, 0x21, 0xC1, 0x41, 0x81, 0x01,

49 0xFE, 0x7E, 0xBE, 0x3E, 0xDE, 0x5E, 0x9E, 0x1E, 0xEE, 0x6E, 0xAE, 0x2E, 0xCE, 0x4E, 0x8E, 0x0E,

50 0xF6, 0x76, 0xB6, 0x36, 0xD6, 0x56, 0x96, 0x16, 0xE6, 0x66, 0xA6, 0x26, 0xC6, 0x46, 0x86, 0x06,

51 0xFA, 0x7A, 0xBA, 0x3A, 0xDA, 0x5A, 0x9A, 0x1A, 0xEA, 0x6A, 0xAA, 0x2A, 0xCA, 0x4A, 0x8A, 0x0A,

52 0xF2, 0x72, 0xB2, 0x32, 0xD2, 0x52, 0x92, 0x12, 0xE2, 0x62, 0xA2, 0x22, 0xC2, 0x42, 0x82, 0x02,

53 0xFC, 0x7C, 0xBC, 0x3C, 0xDC, 0x5C, 0x9C, 0x1C, 0xEC, 0x6C, 0xAC, 0x2C, 0xCC, 0x4C, 0x8C, 0x0C,

54 0xF4, 0x74, 0xB4, 0x34, 0xD4, 0x54, 0x94, 0x14, 0xE4, 0x64, 0xA4, 0x24, 0xC4, 0x44, 0x84, 0x04,

55 0xF8, 0x78, 0xB8, 0x38, 0xD8, 0x58, 0x98, 0x18, 0xE8, 0x68, 0xA8, 0x28, 0xC8, 0x48, 0x88, 0x08,

56 0xF0, 0x70, 0xB0, 0x30, 0xD0, 0x50, 0x90, 0x10, 0xE0, 0x60, 0xA0, 0x20, 0xC0, 0x40, 0x80, 0x00,

57 };

59 typedef struct {

60 int y, pl, x, vdup;

61 } State;

63 static void put_lines_bits(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p)

64 {

65 int pl_byte = state->pl / 8;

66 int pl_bit = state->pl & 7;

67 for (int y = 0; y < state->vdup && (state->y + y) < avctx->height; y++)

68 for (int x = 0; x < row_width; x++)

69 for (int i = 7; i >= 0 && x * 8 + 7 - i < avctx->width; i--)

70 p->data[0][ (state->y + y) * p->linesize[0] + (x * 8 + 7 - i) * pixel_size + pl_byte] |= !!(row[x] & (1 << i)) << pl_bit;

72 state->pl++;

73 if (state->pl >= planes) {

74 state->pl = 0;

75 state->y += state->vdup;

76 state->vdup = 1;

77 }

78 }

80 static void put_lines_bytes(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p)

81 {

82 for (int y = 0; y < state->vdup && (state->y + y) < avctx->height; y++)

83 memcpy(p->data[0] + (state->y + y) * p->linesize[0], row, avctx->width * pixel_size);

85 state->y += state->vdup;

86 state->vdup = 1;

87 }

89 static int gem_decode_frame(AVCodecContext *avctx, AVFrame *p,

90 int *got_frame, AVPacket *avpkt)

91 {

92 const uint8_t *buf = avpkt->data;

93 int buf_size = avpkt->size;

94 const uint8_t *buf_end = buf + buf_size;

95 int header_size, planes, pattern_size, tag = 0, count_scalar = 1, ret;

96 unsigned int x, count, v;

97 GetByteContext gb;

98 uint32_t *palette;

99 const uint8_t * b;

100 uint8_t * row;

101 int row_width, pixel_size;

102 State state = {.y = 0, .pl = 0, .x = 0, .vdup = 1};

103 void (*put_lines)(AVCodecContext *avctx, int planes, int row_width, int pixel_size, State * state, uint8_t * row, AVFrame *p);

104 int width, height;

105

106 if (buf_size <= 16)

107 return AVERROR_INVALIDDATA;

108

109 bytestream2_init(&gb, buf + 2, buf_size - 2);

110 header_size = bytestream2_get_be16(&gb);

111 if (header_size < 8 || buf_size <= header_size * 2)

112 return AVERROR_INVALIDDATA;

113

114 planes = bytestream2_get_be16(&gb);

115 pattern_size = bytestream2_get_be16(&gb);

116 avctx->sample_aspect_ratio.num = bytestream2_get_be16(&gb);

117 avctx->sample_aspect_ratio.den = bytestream2_get_be16(&gb);

118 width = bytestream2_get_be16(&gb);

119 height = bytestream2_get_be16(&gb);

120 ret = ff_set_dimensions(avctx, width, height);

121 if (ret < 0)

122 return ret;

123

124 row_width = (avctx->width + 7) / 8;

125 put_lines = put_lines_bits;

126

127 if (header_size == 9) {

128 count_scalar = bytestream2_get_be16(&gb);

129 if (count_scalar != 3) {

130 avpriv_request_sample(avctx, "count_scalar=%d", count_scalar);

131 return AVERROR_PATCHWELCOME;

132 }

133 planes = 24;

134 avctx->pix_fmt = AV_PIX_FMT_BGR24;

135 pixel_size = 3;

136 } else if (planes == 15) {

137 #if HAVE_BIGENDIAN

138 avctx->pix_fmt = AV_PIX_FMT_BGR555BE;

139 #else

140 avctx->pix_fmt = AV_PIX_FMT_BGR555LE;

141 #endif

142 pixel_size = 2;

143 } else if (planes == 16) {

144 avctx->pix_fmt = AV_PIX_FMT_RGB565BE;

145 pixel_size = 2;

146 } else if (planes == 24) {

147 avctx->pix_fmt = AV_PIX_FMT_RGB24;

148 pixel_size = 3;

149 } else if (planes == 32) {

150 avctx->pix_fmt = AV_PIX_FMT_0RGB;

151 pixel_size = 4;

152 } else {

153 avctx->pix_fmt = AV_PIX_FMT_PAL8;

154 pixel_size = 1;

155 }

156

157 if (header_size >= 11)

158 tag = bytestream2_peek_be32(&gb);

159

160 if (tag == AV_RB32("STTT")) {

161 if (planes != 4) {

162 avpriv_request_sample(avctx, "STTT planes=%d", planes);

163 return AVERROR_PATCHWELCOME;

164 }

165 } else if (tag == AV_RB32("TIMG")) {

166 if (planes != 15) {

167 avpriv_request_sample(avctx, "TIMG planes=%d", planes);

168 return AVERROR_PATCHWELCOME;

169 }

170 } else if (tag == AV_RB32("XIMG")) {

171 if (planes != 1 && planes != 2 && planes != 4 && planes != 8 && planes != 16 && planes != 24 && planes != 32) {

172 avpriv_request_sample(avctx, "XIMG planes=%d", planes);

173 return AVERROR_PATCHWELCOME;

174 }

175 } else if (planes != 1 && planes != 2 && planes != 3 && planes != 4 && planes != 8 && planes != 16 && planes != 24) {

176 avpriv_request_sample(avctx, "planes=%d", planes);

177 return AVERROR_PATCHWELCOME;

178 }

179

180 if ((ret = ff_get_buffer(avctx, p, 0)) < 0)

181 return ret;

182

183 p->pict_type = AV_PICTURE_TYPE_I;

184 p->flags |= AV_FRAME_FLAG_KEY;

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

353 const FFCodec ff_gem_decoder = {

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,

359 FF_CODEC_DECODE_CB(gem_decode_frame),

360 .close = gem_close,

361 };

ff_gem_decoder

const FFCodec ff_gem_decoder

Definition: gemdec.c:353

const char * r

Definition: vf_curves.c:127

GetByteContext

Definition: bytestream.h:33

planes

static const struct @532 planes[]

AVFrame

This structure describes decoded (raw) audio or video data.

Definition: frame.h:427

AVPacket::data

uint8_t * data

Definition: packet.h:558

#define b

Definition: input.c:42

FFCodec

Definition: codec_internal.h:127

AV_PIX_FMT_BGR24

@ AV_PIX_FMT_BGR24

packed RGB 8:8:8, 24bpp, BGRBGR...

Definition: pixfmt.h:76

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

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:40

PUT

#define PUT(v)

FFCodec::p

AVCodec p

The public AVCodec.

Definition: codec_internal.h:131

AVRational::num

int num

Numerator.

Definition: rational.h:59

av_cold

#define av_cold

Definition: attributes.h:106

AV_FRAME_FLAG_KEY

#define AV_FRAME_FLAG_KEY

A flag to mark frames that are keyframes.

Definition: frame.h:642

gem_color_palette

static const uint32_t gem_color_palette[16]

Definition: gemdec.c:33

FF_CODEC_DECODE_CB

#define FF_CODEC_DECODE_CB(func)

Definition: codec_internal.h:346

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:63

const char * g

Definition: vf_curves.c:128

av_assert0

#define av_assert0(cond)

assert() equivalent, that is always enabled.

Definition: avassert.h:41

decode.h

CODEC_LONG_NAME

#define CODEC_LONG_NAME(str)

Definition: codec_internal.h:331

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:278

gem_decode_frame

static int gem_decode_frame(AVCodecContext *avctx, AVFrame *p, int *got_frame, AVPacket *avpkt)

Definition: gemdec.c:89

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:119

State::y

int y

Definition: gemdec.c:60

State

Encoder states.

Definition: libxeve.c:60

ff_get_buffer

int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)

Get a buffer for a frame.

Definition: decode.c:1720

AV_PIX_FMT_RGB24

@ AV_PIX_FMT_RGB24

packed RGB 8:8:8, 24bpp, RGBRGB...

Definition: pixfmt.h:75

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:559

height

#define height

Definition: dsp.h:89

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

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:225

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:80

State

Definition: gemdec.c:59

#define i(width, name, range_min, range_max)

Definition: cbs_h2645.c:256

AVCodec::name

const char * name

Name of the codec implementation.

Definition: codec.h:179

AVCodecContext::height

int height

Definition: avcodec.h:592

AVCodecContext::pix_fmt

enum AVPixelFormat pix_fmt

Pixel format, see AV_PIX_FMT_xxx.

Definition: avcodec.h:631

avcodec.h

AV_PIX_FMT_PAL8

@ AV_PIX_FMT_PAL8

8 bits with AV_PIX_FMT_RGB32 palette

Definition: pixfmt.h:84

state

static struct @531 state

tag

uint32_t tag

Definition: movenc.c:1957

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:431

AVRational::den

int den

Denominator.

Definition: rational.h:60

Windows::Graphics::DirectX::Direct3D11::p

IDirect3DDxgiInterfaceAccess _COM_Outptr_ void ** p

Definition: vsrc_gfxcapture_winrt.hpp:53

AV_PIX_FMT_RGB565BE

@ AV_PIX_FMT_RGB565BE

packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), big-endian

Definition: pixfmt.h:112

AVMEDIA_TYPE_VIDEO

@ AVMEDIA_TYPE_VIDEO

Definition: avutil.h:200

SKIP

#define SKIP

mem.h

AV_CODEC_ID_GEM

@ AV_CODEC_ID_GEM

Definition: codec_id.h:315

avpriv_request_sample

#define avpriv_request_sample(...)

Definition: tableprint_vlc.h:37

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:120

AVCodecContext::priv_data

void * priv_data

Definition: avcodec.h:458

AVPacket

This structure stores compressed data.

Definition: packet.h:535

av_freep

#define av_freep(p)

Definition: tableprint_vlc.h:35

AVCodecContext::width

int width

picture width / height.

Definition: avcodec.h:592

bytestream.h

bytestream2_init

static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size)

Definition: bytestream.h:137

AV_PIX_FMT_0RGB

@ AV_PIX_FMT_0RGB

packed RGB 8:8:8, 32bpp, XRGBXRGB... X=unused/undefined

Definition: pixfmt.h:262

AVERROR_INVALIDDATA

#define AVERROR_INVALIDDATA

Invalid data found when processing input.

Definition: error.h:61

width

#define width

Definition: dsp.h:89

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:616

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