FFmpeg: libavcodec/ljpegenc.c Source File

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ljpegenc.c

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1 /*

2 * lossless JPEG encoder

6 *

7 * Support for external huffman table, various fixes (AVID workaround),

8 * aspecting, new decode_frame mechanism and apple mjpeg-b support

9 * by Alex Beregszaszi

10 *

11 * This file is part of FFmpeg.

12 *

13 * FFmpeg is free software; you can redistribute it and/or

14 * modify it under the terms of the GNU Lesser General Public

15 * License as published by the Free Software Foundation; either

16 * version 2.1 of the License, or (at your option) any later version.

17 *

18 * FFmpeg is distributed in the hope that it will be useful,

19 * but WITHOUT ANY WARRANTY; without even the implied warranty of

20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

21 * Lesser General Public License for more details.

22 *

23 * You should have received a copy of the GNU Lesser General Public

24 * License along with FFmpeg; if not, write to the Free Software

25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

26 */

28 /**

29 * @file

30 * lossless JPEG encoder.

31 */

33 #include "libavutil/frame.h"

34 #include "libavutil/mem.h"

35 #include "libavutil/pixdesc.h"

37 #include "avcodec.h"

38 #include "idctdsp.h"

39 #include "internal.h"

40 #include "mjpegenc_common.h"

41 #include "mpegvideo.h"

42 #include "mjpeg.h"

43 #include "mjpegenc.h"

45 typedef struct LJpegEncContext {

46 IDCTDSPContext idsp;

47 ScanTable scantable;

48 uint16_t matrix[64];

50 int vsample[3];

51 int hsample[3];

53 uint16_t huff_code_dc_luminance[12];

54 uint16_t huff_code_dc_chrominance[12];

55 uint8_t huff_size_dc_luminance[12];

56 uint8_t huff_size_dc_chrominance[12];

58 uint16_t (*scratch)[4];

59 } LJpegEncContext;

61 static int ljpeg_encode_bgr(AVCodecContext *avctx, PutBitContext *pb,

62 const AVFrame *frame)

63 {

64 LJpegEncContext *s = avctx->priv_data;

65 const int width = frame->width;

66 const int height = frame->height;

67 const int linesize = frame->linesize[0];

68 uint16_t (*buffer)[4] = s->scratch;

69 const int predictor = avctx->prediction_method+1;

70 int left[3], top[3], topleft[3];

71 int x, y, i;

73 for (i = 0; i < 3; i++)

74 buffer[0][i] = 1 << (9 - 1);

76 for (y = 0; y < height; y++) {

77 const int modified_predictor = y ? predictor : 1;

78 uint8_t *ptr = frame->data[0] + (linesize * y);

80 if (pb->buf_end - pb->buf - (put_bits_count(pb) >> 3) < width * 3 * 4) {

81 av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");

82 return -1;

83 }

85 for (i = 0; i < 3; i++)

86 top[i]= left[i]= topleft[i]= buffer[0][i];

88 for (x = 0; x < width; x++) {

89 if(avctx->pix_fmt == AV_PIX_FMT_BGR24){

90 buffer[x][1] = ptr[3 * x + 0] - ptr[3 * x + 1] + 0x100;

91 buffer[x][2] = ptr[3 * x + 2] - ptr[3 * x + 1] + 0x100;

92 buffer[x][0] = (ptr[3 * x + 0] + 2 * ptr[3 * x + 1] + ptr[3 * x + 2]) >> 2;

93 }else{

94 buffer[x][1] = ptr[4 * x + 0] - ptr[4 * x + 1] + 0x100;

95 buffer[x][2] = ptr[4 * x + 2] - ptr[4 * x + 1] + 0x100;

96 buffer[x][0] = (ptr[4 * x + 0] + 2 * ptr[4 * x + 1] + ptr[4 * x + 2]) >> 2;

97 }

99 for (i = 0; i < 3; i++) {

100 int pred, diff;

101

102 PREDICT(pred, topleft[i], top[i], left[i], modified_predictor);

103

104 topleft[i] = top[i];

105 top[i] = buffer[x+1][i];

106

107 left[i] = buffer[x][i];

108

109 diff = ((left[i] - pred + 0x100) & 0x1FF) - 0x100;

110

111 if (i == 0)

112 ff_mjpeg_encode_dc(pb, diff, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly

113 else

114 ff_mjpeg_encode_dc(pb, diff, s->huff_size_dc_chrominance, s->huff_code_dc_chrominance);

115 }

116 }

117 }

118

119 return 0;

120 }

121

122 static inline void ljpeg_encode_yuv_mb(LJpegEncContext *s, PutBitContext *pb,

123 const AVFrame *frame, int predictor,

124 int mb_x, int mb_y)

125 {

126 int i;

127

128 if (mb_x == 0 || mb_y == 0) {

129 for (i = 0; i < 3; i++) {

130 uint8_t *ptr;

131 int x, y, h, v, linesize;

132 h = s->hsample[i];

133 v = s->vsample[i];

134 linesize = frame->linesize[i];

135

136 for (y = 0; y < v; y++) {

137 for (x = 0; x < h; x++) {

138 int pred;

139

140 ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap

141 if (y == 0 && mb_y == 0) {

142 if (x == 0 && mb_x == 0)

143 pred = 128;

144 else

145 pred = ptr[-1];

146 } else {

147 if (x == 0 && mb_x == 0) {

148 pred = ptr[-linesize];

149 } else {

150 PREDICT(pred, ptr[-linesize - 1], ptr[-linesize],

151 ptr[-1], predictor);

152 }

153 }

154

155 if (i == 0)

156 ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly

157 else

158 ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_chrominance, s->huff_code_dc_chrominance);

159 }

160 }

161 }

162 } else {

163 for (i = 0; i < 3; i++) {

164 uint8_t *ptr;

165 int x, y, h, v, linesize;

166 h = s->hsample[i];

167 v = s->vsample[i];

168 linesize = frame->linesize[i];

169

170 for (y = 0; y < v; y++) {

171 for (x = 0; x < h; x++) {

172 int pred;

173

174 ptr = frame->data[i] + (linesize * (v * mb_y + y)) + (h * mb_x + x); //FIXME optimize this crap

175 PREDICT(pred, ptr[-linesize - 1], ptr[-linesize], ptr[-1], predictor);

176

177 if (i == 0)

178 ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_luminance, s->huff_code_dc_luminance); //FIXME ugly

179 else

180 ff_mjpeg_encode_dc(pb, *ptr - pred, s->huff_size_dc_chrominance, s->huff_code_dc_chrominance);

181 }

182 }

183 }

184 }

185 }

186

187 static int ljpeg_encode_yuv(AVCodecContext *avctx, PutBitContext *pb,

188 const AVFrame *frame)

189 {

190 const int predictor = avctx->prediction_method + 1;

191 LJpegEncContext *s = avctx->priv_data;

192 const int mb_width = (avctx->width + s->hsample[0] - 1) / s->hsample[0];

193 const int mb_height = (avctx->height + s->vsample[0] - 1) / s->vsample[0];

194 int mb_x, mb_y;

195

196 for (mb_y = 0; mb_y < mb_height; mb_y++) {

197 if (pb->buf_end - pb->buf - (put_bits_count(pb) >> 3) <

198 mb_width * 4 * 3 * s->hsample[0] * s->vsample[0]) {

199 av_log(avctx, AV_LOG_ERROR, "encoded frame too large\n");

200 return -1;

201 }

202

203 for (mb_x = 0; mb_x < mb_width; mb_x++)

204 ljpeg_encode_yuv_mb(s, pb, frame, predictor, mb_x, mb_y);

205 }

206

207 return 0;

208 }

209

210 static int ljpeg_encode_frame(AVCodecContext *avctx, AVPacket *pkt,

211 const AVFrame *pict, int *got_packet)

212 {

213 LJpegEncContext *s = avctx->priv_data;

214 PutBitContext pb;

215 const int width = avctx->width;

216 const int height = avctx->height;

217 const int mb_width = (width + s->hsample[0] - 1) / s->hsample[0];

218 const int mb_height = (height + s->vsample[0] - 1) / s->vsample[0];

219 int max_pkt_size = FF_MIN_BUFFER_SIZE;

220 int ret, header_bits;

221

222 if( avctx->pix_fmt == AV_PIX_FMT_BGR0

223 || avctx->pix_fmt == AV_PIX_FMT_BGRA

224 || avctx->pix_fmt == AV_PIX_FMT_BGR24)

225 max_pkt_size += width * height * 3 * 4;

226 else {

227 max_pkt_size += mb_width * mb_height * 3 * 4

228 * s->hsample[0] * s->vsample[0];

229 }

230

231 if ((ret = ff_alloc_packet2(avctx, pkt, max_pkt_size)) < 0)

232 return ret;

233

234 init_put_bits(&pb, pkt->data, pkt->size);

235

236 ff_mjpeg_encode_picture_header(avctx, &pb, &s->scantable,

237 s->matrix, s->matrix);

238

239 header_bits = put_bits_count(&pb);

240

241 if( avctx->pix_fmt == AV_PIX_FMT_BGR0

242 || avctx->pix_fmt == AV_PIX_FMT_BGRA

243 || avctx->pix_fmt == AV_PIX_FMT_BGR24)

244 ret = ljpeg_encode_bgr(avctx, &pb, pict);

245 else

246 ret = ljpeg_encode_yuv(avctx, &pb, pict);

247 if (ret < 0)

248 return ret;

249

250 emms_c();

251

252 ff_mjpeg_escape_FF(&pb, header_bits >> 3);

253 ff_mjpeg_encode_picture_trailer(&pb, header_bits);

254

255 flush_put_bits(&pb);

256 pkt->size = put_bits_ptr(&pb) - pb.buf;

257 pkt->flags |= AV_PKT_FLAG_KEY;

258 *got_packet = 1;

259

260 return 0;

261 }

262

263 static av_cold int ljpeg_encode_close(AVCodecContext *avctx)

264 {

265 LJpegEncContext *s = avctx->priv_data;

266

267 av_frame_free(&avctx->coded_frame);

268 av_freep(&s->scratch);

269

270 return 0;

271 }

272

273 static av_cold int ljpeg_encode_init(AVCodecContext *avctx)

274 {

275 LJpegEncContext *s = avctx->priv_data;

276

277 if ((avctx->pix_fmt == AV_PIX_FMT_YUV420P ||

278 avctx->pix_fmt == AV_PIX_FMT_YUV422P ||

279 avctx->pix_fmt == AV_PIX_FMT_YUV444P ||

280 avctx->color_range == AVCOL_RANGE_MPEG) &&

281 avctx->strict_std_compliance > FF_COMPLIANCE_UNOFFICIAL) {

282 av_log(avctx, AV_LOG_ERROR,

283 "Limited range YUV is non-standard, set strict_std_compliance to "

284 "at least unofficial to use it.\n");

285 return AVERROR(EINVAL);

286 }

287

288 avctx->coded_frame = av_frame_alloc();

289 if (!avctx->coded_frame)

290 return AVERROR(ENOMEM);

291

292 avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;

293 avctx->coded_frame->key_frame = 1;

294

295 s->scratch = av_malloc_array(avctx->width + 1, sizeof(*s->scratch));

296 if (!s->scratch)

297 goto fail;

298

299 ff_idctdsp_init(&s->idsp, avctx);

300 ff_init_scantable(s->idsp.idct_permutation, &s->scantable,

301 ff_zigzag_direct);

302

303 ff_mjpeg_init_hvsample(avctx, s->hsample, s->vsample);

304

305 ff_mjpeg_build_huffman_codes(s->huff_size_dc_luminance,

306 s->huff_code_dc_luminance,

307 avpriv_mjpeg_bits_dc_luminance,

308 avpriv_mjpeg_val_dc);

309 ff_mjpeg_build_huffman_codes(s->huff_size_dc_chrominance,

310 s->huff_code_dc_chrominance,

311 avpriv_mjpeg_bits_dc_chrominance,

312 avpriv_mjpeg_val_dc);

313

314 return 0;

315 fail:

316 ljpeg_encode_close(avctx);

317 return AVERROR(ENOMEM);

318 }

319

320 AVCodec ff_ljpeg_encoder = {

321 .name = "ljpeg",

322 .long_name = NULL_IF_CONFIG_SMALL("Lossless JPEG"),

323 .type = AVMEDIA_TYPE_VIDEO,

324 .id = AV_CODEC_ID_LJPEG,

325 .priv_data_size = sizeof(LJpegEncContext),

326 .init = ljpeg_encode_init,

327 .encode2 = ljpeg_encode_frame,

328 .close = ljpeg_encode_close,

329 .capabilities = CODEC_CAP_FRAME_THREADS | CODEC_CAP_INTRA_ONLY,

330 .pix_fmts = (const enum AVPixelFormat[]){

331 AV_PIX_FMT_BGR24 , AV_PIX_FMT_BGRA , AV_PIX_FMT_BGR0,

332 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,

333 AV_PIX_FMT_YUV420P , AV_PIX_FMT_YUV444P , AV_PIX_FMT_YUV422P,

334 AV_PIX_FMT_NONE},

335 };

Generated on Sun Mar 8 2015 02:34:55 for FFmpeg by doxygen 1.8.2