/libavcodec/assenc.c
http://github.com/FFmpeg/FFmpeg · C · 127 lines · 87 code · 17 blank · 23 comment · 9 complexity · 8f1378299042dbd8c10c5bef90c23608 MD5 · raw file
- /*
- * SSA/ASS encoder
- * Copyright (c) 2010 Aurelien Jacobs <aurel@gnuage.org>
- *
- * This file is part of FFmpeg.
- *
- * FFmpeg is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * FFmpeg is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
- #include <string.h>
- #include "avcodec.h"
- #include "ass.h"
- #include "libavutil/avstring.h"
- #include "libavutil/internal.h"
- #include "libavutil/mem.h"
- typedef struct {
- int id; ///< current event id, ReadOrder field
- } ASSEncodeContext;
- static av_cold int ass_encode_init(AVCodecContext *avctx)
- {
- avctx->extradata = av_malloc(avctx->subtitle_header_size + 1);
- if (!avctx->extradata)
- return AVERROR(ENOMEM);
- memcpy(avctx->extradata, avctx->subtitle_header, avctx->subtitle_header_size);
- avctx->extradata_size = avctx->subtitle_header_size;
- avctx->extradata[avctx->extradata_size] = 0;
- return 0;
- }
- static int ass_encode_frame(AVCodecContext *avctx,
- unsigned char *buf, int bufsize,
- const AVSubtitle *sub)
- {
- ASSEncodeContext *s = avctx->priv_data;
- int i, len, total_len = 0;
- for (i=0; i<sub->num_rects; i++) {
- char ass_line[2048];
- const char *ass = sub->rects[i]->ass;
- long int layer;
- char *p;
- if (sub->rects[i]->type != SUBTITLE_ASS) {
- av_log(avctx, AV_LOG_ERROR, "Only SUBTITLE_ASS type supported.\n");
- return AVERROR(EINVAL);
- }
- #if FF_API_ASS_TIMING
- if (!strncmp(ass, "Dialogue: ", 10)) {
- if (i > 0) {
- av_log(avctx, AV_LOG_ERROR, "ASS encoder supports only one "
- "ASS rectangle field.\n");
- return AVERROR_INVALIDDATA;
- }
- ass += 10; // skip "Dialogue: "
- /* parse Layer field. If it's a Marked field, the content
- * will be "Marked=N" instead of the layer num, so we will
- * have layer=0, which is fine. */
- layer = strtol(ass, &p, 10);
- #define SKIP_ENTRY(ptr) do { \
- char *sep = strchr(ptr, ','); \
- if (sep) \
- ptr = sep + 1; \
- } while (0)
- SKIP_ENTRY(p); // skip layer or marked
- SKIP_ENTRY(p); // skip start timestamp
- SKIP_ENTRY(p); // skip end timestamp
- snprintf(ass_line, sizeof(ass_line), "%d,%ld,%s", ++s->id, layer, p);
- ass_line[strcspn(ass_line, "\r\n")] = 0;
- ass = ass_line;
- }
- #endif
- len = av_strlcpy(buf+total_len, ass, bufsize-total_len);
- if (len > bufsize-total_len-1) {
- av_log(avctx, AV_LOG_ERROR, "Buffer too small for ASS event.\n");
- return AVERROR_BUFFER_TOO_SMALL;
- }
- total_len += len;
- }
- return total_len;
- }
- #if CONFIG_SSA_ENCODER
- AVCodec ff_ssa_encoder = {
- .name = "ssa",
- .long_name = NULL_IF_CONFIG_SMALL("ASS (Advanced SubStation Alpha) subtitle"),
- .type = AVMEDIA_TYPE_SUBTITLE,
- .id = AV_CODEC_ID_ASS,
- .init = ass_encode_init,
- .encode_sub = ass_encode_frame,
- .priv_data_size = sizeof(ASSEncodeContext),
- };
- #endif
- #if CONFIG_ASS_ENCODER
- AVCodec ff_ass_encoder = {
- .name = "ass",
- .long_name = NULL_IF_CONFIG_SMALL("ASS (Advanced SubStation Alpha) subtitle"),
- .type = AVMEDIA_TYPE_SUBTITLE,
- .id = AV_CODEC_ID_ASS,
- .init = ass_encode_init,
- .encode_sub = ass_encode_frame,
- .priv_data_size = sizeof(ASSEncodeContext),
- };
- #endif