FFmpeg: libavcodec/cdxl.c Source File

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libavcodec

cdxl.c

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1 /*

2 * CDXL video 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 * Commodore CDXL video decoder

25 * @author Paul B Mahol

26 */

28 #define UNCHECKED_BITSTREAM_READER 1

30 #include "libavutil/intreadwrite.h"

31 #include "libavutil/imgutils.h"

32 #include "avcodec.h"

33 #include "get_bits.h"

34 #include "internal.h"

36 #define BIT_PLANAR 0x00

37 #define CHUNKY 0x20

38 #define BYTE_PLANAR 0x40

39 #define BIT_LINE 0x80

40 #define BYTE_LINE 0xC0

42 typedef struct CDXLVideoContext {

43 AVCodecContext *avctx;

44 int bpp;

45 int format;

46 int padded_bits;

47 const uint8_t *palette;

48 int palette_size;

49 const uint8_t *video;

50 int video_size;

51 uint8_t *new_video;

52 int new_video_size;

53 } CDXLVideoContext;

55 static av_cold int cdxl_decode_init(AVCodecContext *avctx)

56 {

57 CDXLVideoContext *c = avctx->priv_data;

59 c->new_video_size = 0;

60 c->avctx = avctx;

62 return 0;

63 }

65 static void import_palette(CDXLVideoContext *c, uint32_t *new_palette)

66 {

67 int i;

69 for (i = 0; i < c->palette_size / 2; i++) {

70 unsigned rgb = AV_RB16(&c->palette[i * 2]);

71 unsigned r = ((rgb >> 8) & 0xF) * 0x11;

72 unsigned g = ((rgb >> 4) & 0xF) * 0x11;

73 unsigned b = (rgb & 0xF) * 0x11;

74 AV_WN32(&new_palette[i], (0xFFU << 24) | (r << 16) | (g << 8) | b);

75 }

76 }

78 static void bitplanar2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)

79 {

80 GetBitContext gb;

81 int x, y, plane;

83 if (init_get_bits8(&gb, c->video, c->video_size) < 0)

84 return;

85 for (plane = 0; plane < c->bpp; plane++) {

86 for (y = 0; y < c->avctx->height; y++) {

87 for (x = 0; x < c->avctx->width; x++)

88 out[linesize * y + x] |= get_bits1(&gb) << plane;

89 skip_bits(&gb, c->padded_bits);

90 }

91 }

92 }

94 static void bitline2chunky(CDXLVideoContext *c, int linesize, uint8_t *out)

95 {

96 GetBitContext gb;

97 int x, y, plane;

99 if (init_get_bits8(&gb, c->video, c->video_size) < 0)

100 return;

101 for (y = 0; y < c->avctx->height; y++) {

102 for (plane = 0; plane < c->bpp; plane++) {

103 for (x = 0; x < c->avctx->width; x++)

104 out[linesize * y + x] |= get_bits1(&gb) << plane;

105 skip_bits(&gb, c->padded_bits);

106 }

107 }

108 }

109

110 static void import_format(CDXLVideoContext *c, int linesize, uint8_t *out)

111 {

112 memset(out, 0, linesize * c->avctx->height);

113

114 switch (c->format) {

115 case BIT_PLANAR:

116 bitplanar2chunky(c, linesize, out);

117 break;

118 case BIT_LINE:

119 bitline2chunky(c, linesize, out);

120 break;

121 }

122 }

123

124 static void cdxl_decode_rgb(CDXLVideoContext *c, AVFrame *frame)

125 {

126 uint32_t *new_palette = (uint32_t *)frame->data[1];

127

128 memset(frame->data[1], 0, AVPALETTE_SIZE);

129 import_palette(c, new_palette);

130 import_format(c, frame->linesize[0], frame->data[0]);

131 }

132

133 static void cdxl_decode_ham6(CDXLVideoContext *c, AVFrame *frame)

134 {

135 AVCodecContext *avctx = c->avctx;

136 uint32_t new_palette[16], r, g, b;

137 uint8_t *ptr, *out, index, op;

138 int x, y;

139

140 ptr = c->new_video;

141 out = frame->data[0];

142

143 import_palette(c, new_palette);

144 import_format(c, avctx->width, c->new_video);

145

146 for (y = 0; y < avctx->height; y++) {

147 r = new_palette[0] & 0xFF0000;

148 g = new_palette[0] & 0xFF00;

149 b = new_palette[0] & 0xFF;

150 for (x = 0; x < avctx->width; x++) {

151 index = *ptr++;

152 op = index >> 4;

153 index &= 15;

154 switch (op) {

155 case 0:

156 r = new_palette[index] & 0xFF0000;

157 g = new_palette[index] & 0xFF00;

158 b = new_palette[index] & 0xFF;

159 break;

160 case 1:

161 b = index * 0x11;

162 break;

163 case 2:

164 r = index * 0x11 << 16;

165 break;

166 case 3:

167 g = index * 0x11 << 8;

168 break;

169 }

170 AV_WL24(out + x * 3, r | g | b);

171 }

172 out += frame->linesize[0];

173 }

174 }

175

176 static void cdxl_decode_ham8(CDXLVideoContext *c, AVFrame *frame)

177 {

178 AVCodecContext *avctx = c->avctx;

179 uint32_t new_palette[64], r, g, b;

180 uint8_t *ptr, *out, index, op;

181 int x, y;

182

183 ptr = c->new_video;

184 out = frame->data[0];

185

186 import_palette(c, new_palette);

187 import_format(c, avctx->width, c->new_video);

188

189 for (y = 0; y < avctx->height; y++) {

190 r = new_palette[0] & 0xFF0000;

191 g = new_palette[0] & 0xFF00;

192 b = new_palette[0] & 0xFF;

193 for (x = 0; x < avctx->width; x++) {

194 index = *ptr++;

195 op = index >> 6;

196 index &= 63;

197 switch (op) {

198 case 0:

199 r = new_palette[index] & 0xFF0000;

200 g = new_palette[index] & 0xFF00;

201 b = new_palette[index] & 0xFF;

202 break;

203 case 1:

204 b = (index << 2) | (b & 3);

205 break;

206 case 2:

207 r = (index << 18) | (r & (3 << 16));

208 break;

209 case 3:

210 g = (index << 10) | (g & (3 << 8));

211 break;

212 }

213 AV_WL24(out + x * 3, r | g | b);

214 }

215 out += frame->linesize[0];

216 }

217 }

218

219 static int cdxl_decode_frame(AVCodecContext *avctx, void *data,

220 int *got_frame, AVPacket *pkt)

221 {

222 CDXLVideoContext *c = avctx->priv_data;

223 AVFrame * const p = data;

224 int ret, w, h, encoding, aligned_width, buf_size = pkt->size;

225 const uint8_t *buf = pkt->data;

226

227 if (buf_size < 32)

228 return AVERROR_INVALIDDATA;

229 encoding = buf[1] & 7;

230 c->format = buf[1] & 0xE0;

231 w = AV_RB16(&buf[14]);

232 h = AV_RB16(&buf[16]);

233 c->bpp = buf[19];

234 c->palette_size = AV_RB16(&buf[20]);

235 c->palette = buf + 32;

236 c->video = c->palette + c->palette_size;

237 c->video_size = buf_size - c->palette_size - 32;

238

239 if (c->palette_size > 512)

240 return AVERROR_INVALIDDATA;

241 if (buf_size < c->palette_size + 32)

242 return AVERROR_INVALIDDATA;

243 if (c->bpp < 1)

244 return AVERROR_INVALIDDATA;

245 if (c->format != BIT_PLANAR && c->format != BIT_LINE) {

246 avpriv_request_sample(avctx, "Pixel format 0x%0x", c->format);

247 return AVERROR_PATCHWELCOME;

248 }

249

250 if ((ret = ff_set_dimensions(avctx, w, h)) < 0)

251 return ret;

252

253 aligned_width = FFALIGN(c->avctx->width, 16);

254 c->padded_bits = aligned_width - c->avctx->width;

255 if (c->video_size < aligned_width * avctx->height * c->bpp / 8)

256 return AVERROR_INVALIDDATA;

257 if (!encoding && c->palette_size && c->bpp <= 8) {

258 avctx->pix_fmt = AV_PIX_FMT_PAL8;

259 } else if (encoding == 1 && (c->bpp == 6 || c->bpp == 8)) {

260 if (c->palette_size != (1 << (c->bpp - 1)))

261 return AVERROR_INVALIDDATA;

262 avctx->pix_fmt = AV_PIX_FMT_BGR24;

263 } else {

264 avpriv_request_sample(avctx, "Encoding %d and bpp %d",

265 encoding, c->bpp);

266 return AVERROR_PATCHWELCOME;

267 }

268

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

270 return ret;

271 p->pict_type = AV_PICTURE_TYPE_I;

272

273 if (encoding) {

274 av_fast_padded_malloc(&c->new_video, &c->new_video_size,

275 h * w + FF_INPUT_BUFFER_PADDING_SIZE);

276 if (!c->new_video)

277 return AVERROR(ENOMEM);

278 if (c->bpp == 8)

279 cdxl_decode_ham8(c, p);

280 else

281 cdxl_decode_ham6(c, p);

282 } else {

283 cdxl_decode_rgb(c, p);

284 }

285 *got_frame = 1;

286

287 return buf_size;

288 }

289

290 static av_cold int cdxl_decode_end(AVCodecContext *avctx)

291 {

292 CDXLVideoContext *c = avctx->priv_data;

293

294 av_freep(&c->new_video);

295

296 return 0;

297 }

298

299 AVCodec ff_cdxl_decoder = {

300 .name = "cdxl",

301 .long_name = NULL_IF_CONFIG_SMALL("Commodore CDXL video"),

302 .type = AVMEDIA_TYPE_VIDEO,

303 .id = AV_CODEC_ID_CDXL,

304 .priv_data_size = sizeof(CDXLVideoContext),

305 .init = cdxl_decode_init,

306 .close = cdxl_decode_end,

307 .decode = cdxl_decode_frame,

308 .capabilities = CODEC_CAP_DR1,

309 };

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