FFmpeg: libavcodec/pnmdec.c Source File

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libavcodec

pnmdec.c

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1 /*

2 * PNM image format

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 #include "avcodec.h"

23 #include "internal.h"

24 #include "put_bits.h"

25 #include "pnm.h"

28 static int pnm_decode_frame(AVCodecContext *avctx, void *data,

29 int *got_frame, AVPacket *avpkt)

30 {

31 const uint8_t *buf = avpkt->data;

32 int buf_size = avpkt->size;

33 PNMContext * const s = avctx->priv_data;

34 AVFrame * const p = data;

35 int i, j, n, linesize, h, upgrade = 0, is_mono = 0;

36 unsigned char *ptr;

37 int components, sample_len, ret;

39 s->bytestream_start =

40 s->bytestream = (uint8_t *)buf;

41 s->bytestream_end = (uint8_t *)buf + buf_size;

43 if ((ret = ff_pnm_decode_header(avctx, s)) < 0)

44 return ret;

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

47 return ret;

48 p->pict_type = AV_PICTURE_TYPE_I;

49 p->key_frame = 1;

51 switch (avctx->pix_fmt) {

52 default:

53 return AVERROR(EINVAL);

54 case AV_PIX_FMT_RGBA64BE:

55 n = avctx->width * 8;

56 components=4;

57 sample_len=16;

58 goto do_read;

59 case AV_PIX_FMT_RGB48BE:

60 n = avctx->width * 6;

61 components=3;

62 sample_len=16;

63 goto do_read;

64 case AV_PIX_FMT_RGBA:

65 n = avctx->width * 4;

66 components=4;

67 sample_len=8;

68 goto do_read;

69 case AV_PIX_FMT_RGB24:

70 n = avctx->width * 3;

71 components=3;

72 sample_len=8;

73 goto do_read;

74 case AV_PIX_FMT_GRAY8:

75 n = avctx->width;

76 components=1;

77 sample_len=8;

78 if (s->maxval < 255)

79 upgrade = 1;

80 goto do_read;

81 case AV_PIX_FMT_GRAY8A:

82 n = avctx->width * 2;

83 components=2;

84 sample_len=8;

85 goto do_read;

86 case AV_PIX_FMT_GRAY16BE:

87 case AV_PIX_FMT_GRAY16LE:

88 n = avctx->width * 2;

89 components=1;

90 sample_len=16;

91 if (s->maxval < 65535)

92 upgrade = 2;

93 goto do_read;

94 case AV_PIX_FMT_MONOWHITE:

95 case AV_PIX_FMT_MONOBLACK:

96 n = (avctx->width + 7) >> 3;

97 components=1;

98 sample_len=1;

99 is_mono = 1;

100 do_read:

101 ptr = p->data[0];

102 linesize = p->linesize[0];

103 if (s->bytestream + n * avctx->height > s->bytestream_end)

104 return AVERROR_INVALIDDATA;

105 if(s->type < 4 || (is_mono && s->type==7)){

106 for (i=0; i<avctx->height; i++) {

107 PutBitContext pb;

108 init_put_bits(&pb, ptr, linesize);

109 for(j=0; j<avctx->width * components; j++){

110 unsigned int c=0;

111 int v=0;

112 if(s->type < 4)

113 while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))

114 s->bytestream++;

115 if(s->bytestream >= s->bytestream_end)

116 return AVERROR_INVALIDDATA;

117 if (is_mono) {

118 /* read a single digit */

119 v = (*s->bytestream++)&1;

120 } else {

121 /* read a sequence of digits */

122 do {

123 v = 10*v + c;

124 c = (*s->bytestream++) - '0';

125 } while (c <= 9);

126 }

127 put_bits(&pb, sample_len, (((1<<sample_len)-1)*v + (s->maxval>>1))/s->maxval);

128 }

129 flush_put_bits(&pb);

130 ptr+= linesize;

131 }

132 }else{

133 for (i = 0; i < avctx->height; i++) {

134 if (!upgrade)

135 memcpy(ptr, s->bytestream, n);

136 else if (upgrade == 1) {

137 unsigned int j, f = (255 * 128 + s->maxval / 2) / s->maxval;

138 for (j = 0; j < n; j++)

139 ptr[j] = (s->bytestream[j] * f + 64) >> 7;

140 } else if (upgrade == 2) {

141 unsigned int j, v, f = (65535 * 32768 + s->maxval / 2) / s->maxval;

142 for (j = 0; j < n / 2; j++) {

143 v = av_be2ne16(((uint16_t *)s->bytestream)[j]);

144 ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;

145 }

146 }

147 s->bytestream += n;

148 ptr += linesize;

149 }

150 }

151 break;

152 case AV_PIX_FMT_YUV420P:

153 case AV_PIX_FMT_YUV420P9BE:

154 case AV_PIX_FMT_YUV420P10BE:

155 {

156 unsigned char *ptr1, *ptr2;

157

158 n = avctx->width;

159 ptr = p->data[0];

160 linesize = p->linesize[0];

161 if (s->maxval >= 256)

162 n *= 2;

163 if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)

164 return AVERROR_INVALIDDATA;

165 for (i = 0; i < avctx->height; i++) {

166 memcpy(ptr, s->bytestream, n);

167 s->bytestream += n;

168 ptr += linesize;

169 }

170 ptr1 = p->data[1];

171 ptr2 = p->data[2];

172 n >>= 1;

173 h = avctx->height >> 1;

174 for (i = 0; i < h; i++) {

175 memcpy(ptr1, s->bytestream, n);

176 s->bytestream += n;

177 memcpy(ptr2, s->bytestream, n);

178 s->bytestream += n;

179 ptr1 += p->linesize[1];

180 ptr2 += p->linesize[2];

181 }

182 }

183 break;

184 case AV_PIX_FMT_YUV420P16:

185 {

186 uint16_t *ptr1, *ptr2;

187 const int f = (65535 * 32768 + s->maxval / 2) / s->maxval;

188 unsigned int j, v;

189

190 n = avctx->width * 2;

191 ptr = p->data[0];

192 linesize = p->linesize[0];

193 if (s->bytestream + n * avctx->height * 3 / 2 > s->bytestream_end)

194 return AVERROR_INVALIDDATA;

195 for (i = 0; i < avctx->height; i++) {

196 for (j = 0; j < n / 2; j++) {

197 v = av_be2ne16(((uint16_t *)s->bytestream)[j]);

198 ((uint16_t *)ptr)[j] = (v * f + 16384) >> 15;

199 }

200 s->bytestream += n;

201 ptr += linesize;

202 }

203 ptr1 = (uint16_t*)p->data[1];

204 ptr2 = (uint16_t*)p->data[2];

205 n >>= 1;

206 h = avctx->height >> 1;

207 for (i = 0; i < h; i++) {

208 for (j = 0; j < n / 2; j++) {

209 v = av_be2ne16(((uint16_t *)s->bytestream)[j]);

210 ptr1[j] = (v * f + 16384) >> 15;

211 }

212 s->bytestream += n;

213

214 for (j = 0; j < n / 2; j++) {

215 v = av_be2ne16(((uint16_t *)s->bytestream)[j]);

216 ptr2[j] = (v * f + 16384) >> 15;

217 }

218 s->bytestream += n;

219

220 ptr1 += p->linesize[1] / 2;

221 ptr2 += p->linesize[2] / 2;

222 }

223 }

224 break;

225 }

226 *got_frame = 1;

227

228 return s->bytestream - s->bytestream_start;

229 }

230

231

232 #if CONFIG_PGM_DECODER

233 AVCodec ff_pgm_decoder = {

234 .name = "pgm",

235 .type = AVMEDIA_TYPE_VIDEO,

236 .id = AV_CODEC_ID_PGM,

237 .priv_data_size = sizeof(PNMContext),

238 .decode = pnm_decode_frame,

239 .capabilities = CODEC_CAP_DR1,

240 .long_name = NULL_IF_CONFIG_SMALL("PGM (Portable GrayMap) image"),

241 };

242 #endif

243

244 #if CONFIG_PGMYUV_DECODER

245 AVCodec ff_pgmyuv_decoder = {

246 .name = "pgmyuv",

247 .type = AVMEDIA_TYPE_VIDEO,

248 .id = AV_CODEC_ID_PGMYUV,

249 .priv_data_size = sizeof(PNMContext),

250 .decode = pnm_decode_frame,

251 .capabilities = CODEC_CAP_DR1,

252 .long_name = NULL_IF_CONFIG_SMALL("PGMYUV (Portable GrayMap YUV) image"),

253 };

254 #endif

255

256 #if CONFIG_PPM_DECODER

257 AVCodec ff_ppm_decoder = {

258 .name = "ppm",

259 .type = AVMEDIA_TYPE_VIDEO,

260 .id = AV_CODEC_ID_PPM,

261 .priv_data_size = sizeof(PNMContext),

262 .decode = pnm_decode_frame,

263 .capabilities = CODEC_CAP_DR1,

264 .long_name = NULL_IF_CONFIG_SMALL("PPM (Portable PixelMap) image"),

265 };

266 #endif

267

268 #if CONFIG_PBM_DECODER

269 AVCodec ff_pbm_decoder = {

270 .name = "pbm",

271 .type = AVMEDIA_TYPE_VIDEO,

272 .id = AV_CODEC_ID_PBM,

273 .priv_data_size = sizeof(PNMContext),

274 .decode = pnm_decode_frame,

275 .capabilities = CODEC_CAP_DR1,

276 .long_name = NULL_IF_CONFIG_SMALL("PBM (Portable BitMap) image"),

277 };

278 #endif

279

280 #if CONFIG_PAM_DECODER

281 AVCodec ff_pam_decoder = {

282 .name = "pam",

283 .type = AVMEDIA_TYPE_VIDEO,

284 .id = AV_CODEC_ID_PAM,

285 .priv_data_size = sizeof(PNMContext),

286 .decode = pnm_decode_frame,

287 .capabilities = CODEC_CAP_DR1,

288 .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),

289 };

290 #endif

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