srtenc: Add timing-less "subrip" encoder.

Unsurprisingly, if a timing-less subrip decoder is desireable, an
encoder is as well. With this in place, we can move on to remove
the use of the old encoder/decoder with embedded timing and move
all timing handling the (de)muxer where they belong.
Signed-off-by: Philip Langdale <philipl@overt.org>

Changelog

@@ -46,6 +46,7 @@ version next:
 - asetpts filter
 - hue filter
 - ICO muxer
+- SubRip encoder and decoder without embedded timing
 
 
 version 0.11:

libavcodec/Makefile

@@ -409,6 +409,7 @@ OBJS-$(CONFIG_SP5X_DECODER)            += sp5xdec.o mjpegdec.o mjpeg.o
 OBJS-$(CONFIG_SRT_DECODER)             += srtdec.o ass.o
 OBJS-$(CONFIG_SRT_ENCODER)             += srtenc.o ass_split.o
 OBJS-$(CONFIG_SUBRIP_DECODER)          += srtdec.o ass.o
+OBJS-$(CONFIG_SUBRIP_ENCODER)          += srtenc.o ass_split.o
 OBJS-$(CONFIG_SUBVIEWER_DECODER)       += subviewerdec.o ass.o
 OBJS-$(CONFIG_SUNRAST_DECODER)         += sunrast.o
 OBJS-$(CONFIG_SUNRAST_ENCODER)         += sunrastenc.o

libavcodec/allcodecs.c

@@ -415,7 +415,7 @@ void avcodec_register_all(void)
     REGISTER_DECODER (REALTEXT, realtext);
     REGISTER_DECODER (SAMI, sami);
     REGISTER_ENCDEC  (SRT, srt);
-    REGISTER_DECODER (SUBRIP, subrip);
+    REGISTER_ENCDEC  (SUBRIP, subrip);
     REGISTER_DECODER (SUBVIEWER, subviewer);
     REGISTER_ENCDEC  (XSUB, xsub);
 

libavcodec/srtenc.c

@@ -252,16 +252,18 @@ static int srt_encode_frame(AVCodecContext *avctx,
 
         dialog = ff_ass_split_dialog(s->ass_ctx, sub->rects[i]->ass, 0, &num);
         for (; dialog && num--; dialog++) {
-            int sh, sm, ss, sc = 10 * dialog->start;
-            int eh, em, es, ec = 10 * dialog->end;
-            sh = sc/3600000;  sc -= 3600000*sh;
-            sm = sc/  60000;  sc -=   60000*sm;
-            ss = sc/   1000;  sc -=    1000*ss;
-            eh = ec/3600000;  ec -= 3600000*eh;
-            em = ec/  60000;  ec -=   60000*em;
-            es = ec/   1000;  ec -=    1000*es;
-            srt_print(s,"%d\r\n%02d:%02d:%02d,%03d --> %02d:%02d:%02d,%03d\r\n",
-                      ++s->count, sh, sm, ss, sc, eh, em, es, ec);
+            if (avctx->codec->id == CODEC_ID_SRT) {
+                int sh, sm, ss, sc = 10 * dialog->start;
+                int eh, em, es, ec = 10 * dialog->end;
+                sh = sc/3600000;  sc -= 3600000*sh;
+                sm = sc/  60000;  sc -=   60000*sm;
+                ss = sc/   1000;  sc -=    1000*ss;
+                eh = ec/3600000;  ec -= 3600000*eh;
+                em = ec/  60000;  ec -=   60000*em;
+                es = ec/   1000;  ec -=    1000*es;
+                srt_print(s,"%d\r\n%02d:%02d:%02d,%03d --> %02d:%02d:%02d,%03d\r\n",
+                          ++s->count, sh, sm, ss, sc, eh, em, es, ec);
+            }
             s->alignment_applied = 0;
             s->dialog_start = s->ptr - 2;
             srt_style_apply(s, dialog->style);
@@ -289,9 +291,10 @@ static int srt_encode_close(AVCodecContext *avctx)
     return 0;
 }
 
+#if CONFIG_SRT_ENCODER
 AVCodec ff_srt_encoder = {
     .name           = "srt",
-    .long_name      = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
+    .long_name      = NULL_IF_CONFIG_SMALL("SubRip subtitle with embedded timing"),
     .type           = AVMEDIA_TYPE_SUBTITLE,
     .id             = AV_CODEC_ID_SRT,
     .priv_data_size = sizeof(SRTContext),
@@ -299,3 +302,17 @@ AVCodec ff_srt_encoder = {
     .encode         = srt_encode_frame,
     .close          = srt_encode_close,
 };
+#endif
+
+#if CONFIG_SUBRIP_ENCODER
+AVCodec ff_subrip_encoder = {
+    .name           = "subrip",
+    .long_name      = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
+    .type           = AVMEDIA_TYPE_SUBTITLE,
+    .id             = AV_CODEC_ID_SUBRIP,
+    .priv_data_size = sizeof(SRTContext),
+    .init           = srt_encode_init,
+    .encode         = srt_encode_frame,
+    .close          = srt_encode_close,
+};
+#endif

libavcodec/version.h

@@ -27,7 +27,7 @@
  */
 
 #define LIBAVCODEC_VERSION_MAJOR 54
-#define LIBAVCODEC_VERSION_MINOR 52
+#define LIBAVCODEC_VERSION_MINOR 53
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \

libavformat/srtenc.c

@@ -42,6 +42,7 @@ static int srt_write_header(AVFormatContext *avf)
         return AVERROR(EINVAL);
     }
     if (avf->streams[0]->codec->codec_id != AV_CODEC_ID_TEXT &&
+        avf->streams[0]->codec->codec_id != AV_CODEC_ID_SUBRIP &&
         avf->streams[0]->codec->codec_id != AV_CODEC_ID_SRT) {
         av_log(avf, AV_LOG_ERROR,
                "Unsupported subtitles codec: %s\n",

tests/fate/subtitles.mak

@@ -19,6 +19,9 @@ fate-sub-sami: CMD = md5 -i $(SAMPLES)/sub/SAMI_capability_tester.smi -f ass
 FATE_SUBTITLES += fate-sub-srt
 fate-sub-srt: CMD = md5 -i $(SAMPLES)/sub/SubRip_capability_tester.srt -f ass
 
+FATE_SUBTITLES += fate-sub-subripenc
+fate-sub-subripenc: CMD = md5 -i $(SAMPLES)/sub/MovText_capability_tester.mp4 -scodec subrip -f srt
+
 FATE_SUBTITLES += fate-sub-subviewer
 fate-sub-subviewer: CMD = md5 -i $(SAMPLES)/sub/SubViewer_capability_tester.sub -f ass
 

tests/ref/fate/sub-subripenc

+bd520f85238abf9df292374aed54681a