FFmpeg: libavcodec/nuv.c Source File

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libavcodec

nuv.c

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1 /*

2 * NuppelVideo 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 #include <stdio.h>

23 #include <stdlib.h>

24 #include <limits.h>

26 #include "libavutil/bswap.h"

27 #include "libavutil/common.h"

28 #include "libavutil/lzo.h"

29 #include "libavutil/imgutils.h"

30 #include "avcodec.h"

31 #include "internal.h"

32 #include "rtjpeg.h"

34 typedef struct {

35 AVFrame *pic;

36 int codec_frameheader;

37 int quality;

38 int width, height;

39 unsigned int decomp_size;

40 unsigned char *decomp_buf;

41 uint32_t lq[64], cq[64];

42 RTJpegContext rtj;

43 DSPContext dsp;

44 } NuvContext;

46 static const uint8_t fallback_lquant[] = {

47 16, 11, 10, 16, 24, 40, 51, 61,

48 12, 12, 14, 19, 26, 58, 60, 55,

49 14, 13, 16, 24, 40, 57, 69, 56,

50 14, 17, 22, 29, 51, 87, 80, 62,

51 18, 22, 37, 56, 68, 109, 103, 77,

52 24, 35, 55, 64, 81, 104, 113, 92,

53 49, 64, 78, 87, 103, 121, 120, 101,

54 72, 92, 95, 98, 112, 100, 103, 99

55 };

57 static const uint8_t fallback_cquant[] = {

58 17, 18, 24, 47, 99, 99, 99, 99,

59 18, 21, 26, 66, 99, 99, 99, 99,

60 24, 26, 56, 99, 99, 99, 99, 99,

61 47, 66, 99, 99, 99, 99, 99, 99,

62 99, 99, 99, 99, 99, 99, 99, 99,

63 99, 99, 99, 99, 99, 99, 99, 99,

64 99, 99, 99, 99, 99, 99, 99, 99,

65 99, 99, 99, 99, 99, 99, 99, 99

66 };

68 /**

69 * @brief copy frame data from buffer to AVFrame, handling stride.

70 * @param f destination AVFrame

71 * @param src source buffer, does not use any line-stride

72 * @param width width of the video frame

73 * @param height height of the video frame

74 */

75 static void copy_frame(AVFrame *f, const uint8_t *src, int width, int height)

76 {

77 AVPicture pic;

78 avpicture_fill(&pic, src, AV_PIX_FMT_YUV420P, width, height);

79 av_picture_copy((AVPicture *)f, &pic, AV_PIX_FMT_YUV420P, width, height);

80 }

82 /**

83 * @brief extract quantization tables from codec data into our context

84 */

85 static int get_quant(AVCodecContext *avctx, NuvContext *c, const uint8_t *buf,

86 int size)

87 {

88 int i;

89 if (size < 2 * 64 * 4) {

90 av_log(avctx, AV_LOG_ERROR, "insufficient rtjpeg quant data\n");

91 return AVERROR_INVALIDDATA;

92 }

93 for (i = 0; i < 64; i++, buf += 4)

94 c->lq[i] = AV_RL32(buf);

95 for (i = 0; i < 64; i++, buf += 4)

96 c->cq[i] = AV_RL32(buf);

97 return 0;

98 }

100 /**

101 * @brief set quantization tables from a quality value

102 */

103 static void get_quant_quality(NuvContext *c, int quality)

104 {

105 int i;

106 quality = FFMAX(quality, 1);

107 for (i = 0; i < 64; i++) {

108 c->lq[i] = (fallback_lquant[i] << 7) / quality;

109 c->cq[i] = (fallback_cquant[i] << 7) / quality;

110 }

111 }

112

113 static int codec_reinit(AVCodecContext *avctx, int width, int height,

114 int quality)

115 {

116 NuvContext *c = avctx->priv_data;

117 int ret;

118

119 width = FFALIGN(width, 2);

120 height = FFALIGN(height, 2);

121 if (quality >= 0)

122 get_quant_quality(c, quality);

123 if (width != c->width || height != c->height) {

124 // also reserve space for a possible additional header

125 int buf_size = height * width * 3 / 2

126 + FFMAX(AV_LZO_OUTPUT_PADDING, FF_INPUT_BUFFER_PADDING_SIZE)

127 + RTJPEG_HEADER_SIZE;

128 if (buf_size > INT_MAX/8)

129 return -1;

130 if ((ret = av_image_check_size(height, width, 0, avctx)) < 0)

131 return ret;

132 avctx->width = c->width = width;

133 avctx->height = c->height = height;

134 av_fast_malloc(&c->decomp_buf, &c->decomp_size,

135 buf_size);

136 if (!c->decomp_buf) {

137 av_log(avctx, AV_LOG_ERROR,

138 "Can't allocate decompression buffer.\n");

139 return AVERROR(ENOMEM);

140 }

141 ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,

142 c->lq, c->cq);

143 av_frame_unref(c->pic);

144 return 1;

145 } else if (quality != c->quality)

146 ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height,

147 c->lq, c->cq);

148

149 return 0;

150 }

151

152 static int decode_frame(AVCodecContext *avctx, void *data, int *got_frame,

153 AVPacket *avpkt)

154 {

155 const uint8_t *buf = avpkt->data;

156 int buf_size = avpkt->size;

157 NuvContext *c = avctx->priv_data;

158 AVFrame *picture = data;

159 int orig_size = buf_size;

160 int keyframe, ret;

161 int size_change = 0;

162 int result, init_frame = !avctx->frame_number;

163 enum {

164 NUV_UNCOMPRESSED = '0',

165 NUV_RTJPEG = '1',

166 NUV_RTJPEG_IN_LZO = '2',

167 NUV_LZO = '3',

168 NUV_BLACK = 'N',

169 NUV_COPY_LAST = 'L'

170 } comptype;

171

172 if (buf_size < 12) {

173 av_log(avctx, AV_LOG_ERROR, "coded frame too small\n");

174 return AVERROR_INVALIDDATA;

175 }

176

177 // codec data (rtjpeg quant tables)

178 if (buf[0] == 'D' && buf[1] == 'R') {

179 int ret;

180 // skip rest of the frameheader.

181 buf = &buf[12];

182 buf_size -= 12;

183 ret = get_quant(avctx, c, buf, buf_size);

184 if (ret < 0)

185 return ret;

186 ff_rtjpeg_decode_init(&c->rtj, &c->dsp, c->width, c->height, c->lq,

187 c->cq);

188 return orig_size;

189 }

190

191 if (buf_size < 12 || buf[0] != 'V') {

192 av_log(avctx, AV_LOG_ERROR, "not a nuv video frame\n");

193 return AVERROR_INVALIDDATA;

194 }

195 comptype = buf[1];

196 switch (comptype) {

197 case NUV_RTJPEG_IN_LZO:

198 case NUV_RTJPEG:

199 keyframe = !buf[2];

200 break;

201 case NUV_COPY_LAST:

202 keyframe = 0;

203 break;

204 default:

205 keyframe = 1;

206 break;

207 }

208 retry:

209 // skip rest of the frameheader.

210 buf = &buf[12];

211 buf_size -= 12;

212 if (comptype == NUV_RTJPEG_IN_LZO || comptype == NUV_LZO) {

213 int outlen = c->decomp_size - FFMAX(FF_INPUT_BUFFER_PADDING_SIZE, AV_LZO_OUTPUT_PADDING);

214 int inlen = buf_size;

215 if (av_lzo1x_decode(c->decomp_buf, &outlen, buf, &inlen)) {

216 av_log(avctx, AV_LOG_ERROR, "error during lzo decompression\n");

217 return AVERROR_INVALIDDATA;

218 }

219 buf = c->decomp_buf;

220 buf_size = c->decomp_size - FFMAX(FF_INPUT_BUFFER_PADDING_SIZE, AV_LZO_OUTPUT_PADDING) - outlen;

221 }

222 if (c->codec_frameheader) {

223 int w, h, q;

224 if (buf_size < RTJPEG_HEADER_SIZE) {

225 av_log(avctx, AV_LOG_ERROR, "Too small NUV video frame\n");

226 return AVERROR_INVALIDDATA;

227 }

228 // There seem to exist two variants of this header: one starts with 'V'

229 // and 5 bytes unknown, the other matches current MythTV and is 4 bytes size,

230 // 1 byte header size (== 12), 1 byte version (== 0)

231 if (buf[0] != 'V' && AV_RL16(&buf[4]) != 0x000c) {

232 av_log(avctx, AV_LOG_ERROR, "Unknown secondary frame header (wrong codec_tag?)\n");

233 return AVERROR_INVALIDDATA;

234 }

235 w = AV_RL16(&buf[6]);

236 h = AV_RL16(&buf[8]);

237 q = buf[10];

238 if ((result = codec_reinit(avctx, w, h, q)) < 0)

239 return result;

240 if (result) {

241 buf = avpkt->data;

242 buf_size = avpkt->size;

243 size_change = 1;

244 goto retry;

245 }

246 buf = &buf[RTJPEG_HEADER_SIZE];

247 buf_size -= RTJPEG_HEADER_SIZE;

248 }

249

250 if (size_change || keyframe) {

251 av_frame_unref(c->pic);

252 init_frame = 1;

253 }

254

255 if ((result = ff_reget_buffer(avctx, c->pic)) < 0)

256 return result;

257 if (init_frame) {

258 memset(c->pic->data[0], 0, avctx->height * c->pic->linesize[0]);

259 memset(c->pic->data[1], 0x80, avctx->height * c->pic->linesize[1] / 2);

260 memset(c->pic->data[2], 0x80, avctx->height * c->pic->linesize[2] / 2);

261 }

262

263 c->pic->pict_type = keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;

264 c->pic->key_frame = keyframe;

265 // decompress/copy/whatever data

266 switch (comptype) {

267 case NUV_LZO:

268 case NUV_UNCOMPRESSED: {

269 int height = c->height;

270 if (buf_size < c->width * height * 3 / 2) {

271 av_log(avctx, AV_LOG_ERROR, "uncompressed frame too short\n");

272 height = buf_size / c->width / 3 * 2;

273 }

274 if(height > 0)

275 copy_frame(c->pic, buf, c->width, height);

276 break;

277 }

278 case NUV_RTJPEG_IN_LZO:

279 case NUV_RTJPEG:

280 ret = ff_rtjpeg_decode_frame_yuv420(&c->rtj, c->pic, buf, buf_size);

281 if (ret < 0)

282 return ret;

283 break;

284 case NUV_BLACK:

285 memset(c->pic->data[0], 0, c->width * c->height);

286 memset(c->pic->data[1], 128, c->width * c->height / 4);

287 memset(c->pic->data[2], 128, c->width * c->height / 4);

288 break;

289 case NUV_COPY_LAST:

290 /* nothing more to do here */

291 break;

292 default:

293 av_log(avctx, AV_LOG_ERROR, "unknown compression\n");

294 return AVERROR_INVALIDDATA;

295 }

296

297 if ((result = av_frame_ref(picture, c->pic)) < 0)

298 return result;

299

300 *got_frame = 1;

301 return orig_size;

302 }

303

304 static av_cold int decode_init(AVCodecContext *avctx)

305 {

306 NuvContext *c = avctx->priv_data;

307 int ret;

308

309 c->pic = av_frame_alloc();

310 if (!c->pic)

311 return AVERROR(ENOMEM);

312

313 avctx->pix_fmt = AV_PIX_FMT_YUV420P;

314 c->decomp_buf = NULL;

315 c->quality = -1;

316 c->width = 0;

317 c->height = 0;

318

319 c->codec_frameheader = avctx->codec_tag == MKTAG('R', 'J', 'P', 'G');

320

321 if (avctx->extradata_size)

322 get_quant(avctx, c, avctx->extradata, avctx->extradata_size);

323

324 ff_dsputil_init(&c->dsp, avctx);

325

326 if ((ret = codec_reinit(avctx, avctx->width, avctx->height, -1)) < 0)

327 return ret;

328

329 return 0;

330 }

331

332 static av_cold int decode_end(AVCodecContext *avctx)

333 {

334 NuvContext *c = avctx->priv_data;

335

336 av_freep(&c->decomp_buf);

337 av_frame_free(&c->pic);

338

339 return 0;

340 }

341

342 AVCodec ff_nuv_decoder = {

343 .name = "nuv",

344 .long_name = NULL_IF_CONFIG_SMALL("NuppelVideo/RTJPEG"),

345 .type = AVMEDIA_TYPE_VIDEO,

346 .id = AV_CODEC_ID_NUV,

347 .priv_data_size = sizeof(NuvContext),

348 .init = decode_init,

349 .close = decode_end,

350 .decode = decode_frame,

351 .capabilities = CODEC_CAP_DR1,

352 };

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