@@ -267,6 +267,7 @@ static av_cold int init_subtitles(AVFilterContext *ctx, const char *args)

     AVFormatContext *fmt = NULL;

     AVCodecContext *dec_ctx = NULL;

     AVCodec *dec = NULL;

+    AVCodecDescriptor *dec_desc;

     AVStream *st;

     AVPacket pkt;

     AssContext *ass = ctx->priv;

@@ -309,6 +310,12 @@ static av_cold int init_subtitles(AVFilterContext *ctx, const char *args)

                avcodec_get_name(dec_ctx->codec_id));

         return AVERROR(EINVAL);

     }

+    dec_desc = avcodec_descriptor_get(dec_ctx->codec_id);

+    if (dec_desc && (dec_desc->props & AV_CODEC_PROP_BITMAP_SUB)) {

+        av_log(ctx, AV_LOG_ERROR,

+               "Only text based subtitles are currently supported\n");

+        return AVERROR_PATCHWELCOME;

+    }

     if (ass->charenc)

         av_dict_set(&codec_opts, "sub_charenc", ass->charenc, 0);

     ret = avcodec_open2(dec_ctx, dec, &codec_opts);