FFmpeg: libavcodec/ljpegenc.c Source File

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libavcodec

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 "avcodec.h"

34 #include "internal.h"

35 #include "mpegvideo.h"

36 #include "mjpeg.h"

37 #include "mjpegenc.h"

40 static int encode_picture_lossless(AVCodecContext *avctx, AVPacket *pkt,

41 const AVFrame *pict, int *got_packet)

42 {

43 MpegEncContext * const s = avctx->priv_data;

44 MJpegContext * const m = s->mjpeg_ctx;

45 const int width= s->width;

46 const int height= s->height;

47 AVFrame * const p = &s->current_picture.f;

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

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

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

51 int ret, max_pkt_size = FF_MIN_BUFFER_SIZE;

53 if (avctx->pix_fmt == AV_PIX_FMT_BGRA)

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

55 else {

56 max_pkt_size += mb_width * mb_height * 3 * 4

57 * s->mjpeg_hsample[0] * s->mjpeg_vsample[0];

58 }

60 if (!s->edge_emu_buffer &&

61 (ret = ff_mpv_frame_size_alloc(s, pict->linesize[0])) < 0) {

62 av_log(avctx, AV_LOG_ERROR, "failed to allocate context scratch buffers.\n");

63 return ret;

64 }

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

67 return ret;

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

71 av_frame_unref(p);

72 ret = av_frame_ref(p, pict);

73 if (ret < 0)

74 return ret;

75 p->pict_type= AV_PICTURE_TYPE_I;

76 p->key_frame= 1;

78 ff_mjpeg_encode_picture_header(s);

80 s->header_bits= put_bits_count(&s->pb);

82 if(avctx->pix_fmt == AV_PIX_FMT_BGR0

83 || avctx->pix_fmt == AV_PIX_FMT_BGRA

84 || avctx->pix_fmt == AV_PIX_FMT_BGR24){

85 int x, y, i;

86 const int linesize= p->linesize[0];

87 uint16_t (*buffer)[4]= (void *) s->rd_scratchpad;

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

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

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

92 }

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

95 const int modified_predictor= y ? predictor : 1;

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

98 if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < width*3*4){

99 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");

100 return -1;

101 }

102

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

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

105 }

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

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

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

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

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

111 }else{

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

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

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

115 }

116

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

118 int pred, diff;

119

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

121

122 topleft[i]= top[i];

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

124

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

126

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

128

129 if(i==0)

130 ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_luminance, m->huff_code_dc_luminance); //FIXME ugly

131 else

132 ff_mjpeg_encode_dc(s, diff, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);

133 }

134 }

135 }

136 }else{

137 int mb_x, mb_y, i;

138

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

140 if(s->pb.buf_end - s->pb.buf - (put_bits_count(&s->pb)>>3) < mb_width * 4 * 3 * s->mjpeg_hsample[0] * s->mjpeg_vsample[0]){

141 av_log(s->avctx, AV_LOG_ERROR, "encoded frame too large\n");

142 return -1;

143 }

144 for(mb_x = 0; mb_x < mb_width; mb_x++) {

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

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

147 uint8_t *ptr;

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

149 h = s->mjpeg_hsample[i];

150 v = s->mjpeg_vsample[i];

151 linesize= p->linesize[i];

152

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

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

155 int pred;

156

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

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

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

160 pred= 128;

161 }else{

162 pred= ptr[-1];

163 }

164 }else{

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

166 pred= ptr[-linesize];

167 }else{

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

169 }

170 }

171

172 if(i==0)

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

174 else

175 ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);

176 }

177 }

178 }

179 }else{

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

181 uint8_t *ptr;

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

183 h = s->mjpeg_hsample[i];

184 v = s->mjpeg_vsample[i];

185 linesize= p->linesize[i];

186

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

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

189 int pred;

190

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

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

193

194 if(i==0)

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

196 else

197 ff_mjpeg_encode_dc(s, *ptr - pred, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);

198 }

199 }

200 }

201 }

202 }

203 }

204 }

205

206 emms_c();

207 av_assert0(s->esc_pos == s->header_bits >> 3);

208 ff_mjpeg_encode_stuffing(s);

209 ff_mjpeg_encode_picture_trailer(s);

210 s->picture_number++;

211

212 flush_put_bits(&s->pb);

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

214 pkt->flags |= AV_PKT_FLAG_KEY;

215 *got_packet = 1;

216

217 return 0;

218 // return (put_bits_count(&f->pb)+7)/8;

219 }

220

221

222 AVCodec ff_ljpeg_encoder = { //FIXME avoid MPV_* lossless JPEG should not need them

223 .name = "ljpeg",

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

225 .type = AVMEDIA_TYPE_VIDEO,

226 .id = AV_CODEC_ID_LJPEG,

227 .priv_data_size = sizeof(MpegEncContext),

228 .init = ff_MPV_encode_init,

229 .encode2 = encode_picture_lossless,

230 .close = ff_MPV_encode_end,

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

232 AV_PIX_FMT_BGR24, AV_PIX_FMT_BGRA, AV_PIX_FMT_BGR0,

233 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P,

234 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P,

235 AV_PIX_FMT_NONE},

236 };

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