summaryrefslogtreecommitdiffstats
path: root/sub/sd_lavc_conv.c
diff options
context:
space:
mode:
Diffstat (limited to 'sub/sd_lavc_conv.c')
-rw-r--r--sub/sd_lavc_conv.c132
1 files changed, 132 insertions, 0 deletions
diff --git a/sub/sd_lavc_conv.c b/sub/sd_lavc_conv.c
new file mode 100644
index 0000000000..e45e743499
--- /dev/null
+++ b/sub/sd_lavc_conv.c
@@ -0,0 +1,132 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv 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.
+ *
+ * mpv 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 mpv. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdlib.h>
+#include <assert.h>
+
+#include <libavcodec/avcodec.h>
+#include <libavutil/intreadwrite.h>
+#include <libavutil/common.h>
+
+#include "talloc.h"
+#include "core/mp_msg.h"
+#include "core/av_common.h"
+#include "sd.h"
+
+struct sd_lavc_priv {
+ AVCodecContext *avctx;
+};
+
+static bool supports_format(const char *format)
+{
+ enum AVCodecID cid = mp_codec_to_av_codec_id(format);
+ const AVCodecDescriptor *desc = avcodec_descriptor_get(cid);
+ // These are documented to support AVSubtitleRect->ass.
+ return desc && (desc->props & AV_CODEC_PROP_TEXT_SUB);
+}
+
+static int init(struct sd *sd)
+{
+ struct sd_lavc_priv *priv = talloc_zero(NULL, struct sd_lavc_priv);
+ AVCodecContext *avctx = NULL;
+ AVCodec *codec = avcodec_find_decoder(mp_codec_to_av_codec_id(sd->codec));
+ if (!codec)
+ goto error;
+ avctx = avcodec_alloc_context3(codec);
+ if (!avctx)
+ goto error;
+ avctx->extradata_size = sd->extradata_len;
+ avctx->extradata = sd->extradata;
+ if (avcodec_open2(avctx, codec, NULL) < 0)
+ goto error;
+ // Documented as "set by libavcodec", but there is no other way
+ avctx->time_base = (AVRational) {1, 1000};
+ priv->avctx = avctx;
+ sd->priv = priv;
+ sd->output_codec = "ass";
+ sd->output_extradata = avctx->subtitle_header;
+ sd->output_extradata_len = avctx->subtitle_header_size;
+ return 0;
+
+ error:
+ mp_msg(MSGT_SUBREADER, MSGL_ERR,
+ "Could not open libavcodec subtitle converter\n");
+ av_free(avctx);
+ talloc_free(priv);
+ return -1;
+}
+
+static void decode(struct sd *sd, struct demux_packet *packet)
+{
+ struct sd_lavc_priv *priv = sd->priv;
+ AVCodecContext *avctx = priv->avctx;
+ double ts = av_q2d(av_inv_q(avctx->time_base));
+ AVSubtitle sub = {0};
+ AVPacket pkt;
+ int ret, got_sub;
+
+ av_init_packet(&pkt);
+ pkt.data = packet->buffer;
+ pkt.size = packet->len;
+ pkt.pts = packet->pts == MP_NOPTS_VALUE ? AV_NOPTS_VALUE : packet->pts * ts;
+ pkt.duration = packet->duration * ts;
+
+ ret = avcodec_decode_subtitle2(avctx, &sub, &got_sub, &pkt);
+ if (ret < 0) {
+ mp_msg(MSGT_OSD, MSGL_ERR, "Error decoding subtitle\n");
+ } else if (got_sub) {
+ for (int i = 0; i < sub.num_rects; i++) {
+ char *ass_line = sub.rects[i]->ass;
+ if (!ass_line)
+ break;
+ // This might contain embedded timestamps, using the "old" ffmpeg
+ // ASS packet format, in which case pts/duration might be ignored
+ // at a later point.
+ sd_conv_add_packet(sd, ass_line, strlen(ass_line),
+ packet->pts, packet->duration);
+ }
+ }
+
+ av_free_packet(&pkt);
+ avsubtitle_free(&sub);
+}
+
+static void reset(struct sd *sd)
+{
+ struct sd_lavc_priv *priv = sd->priv;
+
+ avcodec_flush_buffers(priv->avctx);
+ sd_conv_def_reset(sd);
+}
+
+static void uninit(struct sd *sd)
+{
+ struct sd_lavc_priv *priv = sd->priv;
+
+ avcodec_close(priv->avctx);
+ av_free(priv->avctx);
+ talloc_free(priv);
+}
+
+const struct sd_functions sd_lavc_conv = {
+ .supports_format = supports_format,
+ .init = init,
+ .decode = decode,
+ .get_converted = sd_conv_def_get_converted,
+ .reset = reset,
+ .uninit = uninit,
+};