mpv/sub/av_sub.c

/*
 * This file is part of MPlayer.
 *
 * MPlayer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * MPlayer 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with MPlayer; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <libavcodec/avcodec.h>

#include "mp_msg.h"
#include "libmpdemux/stheader.h"
#include "sub.h"
#include "spudec.h"
#include "av_sub.h"

void reset_avsub(struct sh_sub *sh)
{
    if (sh->context) {
        avcodec_close(sh->context);
        av_freep(&sh->context);
    }
}

/**
 * Decode a subtitle packet via libavcodec.
 * \return < 0 on error, > 0 if further processing is needed
 */
int decode_avsub(struct sh_sub *sh, uint8_t *data, int size,
                 double pts, double duration)
{
    AVCodecContext *ctx = sh->context;
    enum CodecID cid = CODEC_ID_NONE;
    int res;
    int got_sub;
    AVSubtitle sub;
    AVPacket pkt;

    switch (sh->type) {
    case 'b':
        cid = CODEC_ID_DVB_SUBTITLE; break;
    case 'p':
        cid = CODEC_ID_HDMV_PGS_SUBTITLE; break;
    case 'x':
        cid = CODEC_ID_XSUB; break;
    }

    av_init_packet(&pkt);
    pkt.data = data;
    pkt.size = size;
    pkt.pts = pts * 1000;
    if (duration >= 0)
        pkt.convergence_duration = duration * 1000;
    if (!ctx) {
        AVCodec *sub_codec;
        ctx = avcodec_alloc_context();
        sub_codec = avcodec_find_decoder(cid);
        if (!ctx || !sub_codec || avcodec_open(ctx, sub_codec) < 0) {
            mp_msg(MSGT_SUBREADER, MSGL_FATAL,
                   "Could not open subtitle decoder\n");
            av_freep(&ctx);
            return -1;
        }
        sh->context = ctx;
    }
    res = avcodec_decode_subtitle2(ctx, &sub, &got_sub, &pkt);
    if (res < 0)
        return res;
    if (pts != MP_NOPTS_VALUE) {
        if (sub.end_display_time > sub.start_display_time)
            duration = (sub.end_display_time - sub.start_display_time) / 1000.0;
        pts += sub.start_display_time / 1000.0;
    }
    double endpts = MP_NOPTS_VALUE;
    if (pts != MP_NOPTS_VALUE && duration >= 0)
        endpts = pts + duration;
    if (got_sub && vo_spudec && sub.num_rects == 0)
        spudec_set_paletted(vo_spudec, NULL, 0, NULL, 0, 0, 0, 0, pts, endpts);
    if (got_sub && sub.num_rects > 0) {
        switch (sub.rects[0]->type) {
        case SUBTITLE_BITMAP:
            if (!vo_spudec)
                vo_spudec = spudec_new_scaled(NULL, ctx->width, ctx->height, NULL, 0);
            spudec_set_paletted(vo_spudec,
                                sub.rects[0]->pict.data[0],
                                sub.rects[0]->pict.linesize[0],
                                sub.rects[0]->pict.data[1],
                                sub.rects[0]->x,
                                sub.rects[0]->y,
                                sub.rects[0]->w,
                                sub.rects[0]->h,
                                pts,
                                endpts);
            vo_osd_changed(OSDTYPE_SPU);
            break;
        default:
            mp_msg(MSGT_SUBREADER, MSGL_ERR, "sd_avsub: unsupported subtitle "
                   "type from libavcodec\n");
            res = -1;
            break;
        }
    }
#if LIBAVCODEC_VERSION_INT >= AV_VERSION_INT(52, 82, 0)
    if (got_sub)
        avsubtitle_free(&sub);
#endif
    return res;
}