Add bitstream filter to convert between mov and plain text subtitles

Originally committed as revision 11659 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/Makefile

@@ -337,10 +337,12 @@ OBJS-$(CONFIG_DUMP_EXTRADATA_BSF)      += dump_extradata_bsf.o
 OBJS-$(CONFIG_H264_MP4TOANNEXB_BSF)    += h264_mp4toannexb_bsf.o
 OBJS-$(CONFIG_IMX_DUMP_HEADER_BSF)     += imx_dump_header_bsf.o
 OBJS-$(CONFIG_MJPEGA_DUMP_HEADER_BSF)  += mjpega_dump_header_bsf.o
+OBJS-$(CONFIG_MOV2TEXTSUB_BSF)         += movsub_bsf.o
 OBJS-$(CONFIG_MP3_HEADER_COMPRESS_BSF) += mp3_header_compress_bsf.o
 OBJS-$(CONFIG_MP3_HEADER_DECOMPRESS_BSF) += mp3_header_decompress_bsf.o mpegaudiodata.o
 OBJS-$(CONFIG_NOISE_BSF)               += noise_bsf.o
 OBJS-$(CONFIG_REMOVE_EXTRADATA_BSF)    += remove_extradata_bsf.o
+OBJS-$(CONFIG_TEXT2MOVSUB_BSF)         += movsub_bsf.o
 
 OBJS-$(HAVE_BEOSTHREADS)               += beosthread.o
 OBJS-$(HAVE_OS2THREADS)                += os2thread.o

libavcodec/allcodecs.c

@@ -305,7 +305,9 @@ void avcodec_register_all(void)
     REGISTER_BSF     (MJPEGA_DUMP_HEADER, mjpega_dump_header);
     REGISTER_BSF     (MP3_HEADER_COMPRESS, mp3_header_compress);
     REGISTER_BSF     (MP3_HEADER_DECOMPRESS, mp3_header_decompress);
+    REGISTER_BSF     (MOV2TEXTSUB, mov2textsub);
     REGISTER_BSF     (NOISE, noise);
     REGISTER_BSF     (REMOVE_EXTRADATA, remove_extradata);
+    REGISTER_BSF     (TEXT2MOVSUB, text2movsub);
 }
 

libavcodec/movsub_bsf.c

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2008 Reimar Döffinger
+ *
+ * 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 "avcodec.h"
+
+
+static int text2movsub(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
+                     uint8_t **poutbuf, int *poutbuf_size,
+                     const uint8_t *buf, int buf_size, int keyframe){
+    if (buf_size > 0xffff) return 0;
+    *poutbuf_size = buf_size + 2;
+    *poutbuf = av_malloc(*poutbuf_size + FF_INPUT_BUFFER_PADDING_SIZE);
+    AV_WB16(*poutbuf, buf_size);
+    memcpy(*poutbuf + 2, buf, buf_size);
+    return 1;
+}
+
+AVBitStreamFilter text2movsub_bsf={
+    "text2movsub",
+    0,
+    text2movsub,
+};
+
+static int mov2textsub(AVBitStreamFilterContext *bsfc, AVCodecContext *avctx, const char *args,
+                     uint8_t **poutbuf, int *poutbuf_size,
+                     const uint8_t *buf, int buf_size, int keyframe){
+    if (buf_size < 2) return 0;
+    *poutbuf_size = FFMIN(buf_size - 2, AV_RB16(buf));
+    *poutbuf = av_malloc(*poutbuf_size + FF_INPUT_BUFFER_PADDING_SIZE);
+    memcpy(*poutbuf, buf + 2, *poutbuf_size);
+    return 1;
+}
+
+AVBitStreamFilter mov2textsub_bsf={
+    "mov2textsub",
+    0,
+    mov2textsub,
+};