/* * 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 -1;        } #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 -1;        }         total_len += len;    }     return total_len;} #if CONFIG_SSA_ENCODERAVCodec 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_ENCODERAVCodec 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