add SubRip decoder

Originally committed as revision 26119 to svn://svn.ffmpeg.org/ffmpeg/trunk

Changelog

@@ -69,6 +69,7 @@ version <next>:
 - replace the ocv_smooth filter with a more generic ocv filter
 - Windows Televison (WTV) demuxer
 - FFmpeg metadata format muxer and demuxer
+- SubRip (srt) subtitle decoder
 
 
 version 0.6:

MAINTAINERS

@@ -198,6 +198,7 @@ Codecs:
  smc.c Mike Melanson
  snow.c Michael Niedermayer, Loren Merritt
  sonic.c Alex Beregszaszi
+ srtdec.c Aurelien Jacobs
  sunrast.c Ivo van Poorten
  svq3.c Michael Niedermayer
  targa.c Kostya Shishkov

doc/general.texi

@@ -694,7 +694,7 @@ performance on systems without hardware floating point support).
 @item DVB @tab X @tab X @tab X @tab X
 @item DVD @tab X @tab X @tab X @tab X
 @item PGS @tab @tab @tab @tab X
-@item SubRip (SRT) @tab X @tab X
+@item SubRip (SRT) @tab X @tab X @tab @tab X
 @item XSUB @tab @tab @tab X @tab X
 @end multitable
 

libavcodec/Makefile

@@ -337,6 +337,7 @@ OBJS-$(CONFIG_SONIC_DECODER) += sonic.o
 OBJS-$(CONFIG_SONIC_ENCODER) += sonic.o
 OBJS-$(CONFIG_SONIC_LS_ENCODER) += sonic.o
 OBJS-$(CONFIG_SP5X_DECODER) += sp5xdec.o mjpegdec.o mjpeg.o
+OBJS-$(CONFIG_SRT_DECODER) += srtdec.o ass.o
 OBJS-$(CONFIG_SUNRAST_DECODER) += sunrast.o
 OBJS-$(CONFIG_SVQ1_DECODER) += svq1dec.o svq1.o h263.o \
  mpegvideo.o error_resilience.o

libavcodec/allcodecs.c

@@ -347,6 +347,7 @@ void avcodec_register_all(void)
  REGISTER_ENCDEC (DVBSUB, dvbsub);
  REGISTER_ENCDEC (DVDSUB, dvdsub);
  REGISTER_DECODER (PGSSUB, pgssub);
+ REGISTER_DECODER (SRT, srt);
  REGISTER_ENCDEC (XSUB, xsub);
 
  /* external libraries */

libavcodec/ass.c

@@ -22,6 +22,46 @@
 #include "avcodec.h"
 #include "ass.h"
 
+int ff_ass_subtitle_header(AVCodecContext *avctx,
+ const char *font, int font_size,
+ int color, int back_color,
+ int bold, int italic, int underline,
+ int alignment)
+{
+ char header[512];
+
+ snprintf(header, sizeof(header),
+ "[Script Info]\r\n"
+ "ScriptType: v4.00+\r\n"
+ "\r\n"
+ "[V4+ Styles]\r\n"
+ "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding\r\n"
+ "Style: Default,%s,%d,&H%x,&H%x,&H%x,&H%x,%d,%d,%d,1,1,0,%d,10,10,10,0,0\r\n"
+ "\r\n"
+ "[Events]\r\n"
+ "Format: Layer, Start, End, Text\r\n",
+ font, font_size, color, color, back_color, back_color,
+ -bold, -italic, -underline, alignment);
+
+ avctx->subtitle_header = av_strdup(header);
+ if (!avctx->subtitle_header)
+ return AVERROR(ENOMEM);
+ avctx->subtitle_header_size = strlen(avctx->subtitle_header);
+ return 0;
+}
+
+int ff_ass_subtitle_header_default(AVCodecContext *avctx)
+{
+ return ff_ass_subtitle_header(avctx, ASS_DEFAULT_FONT,
+ ASS_DEFAULT_FONT_SIZE,
+ ASS_DEFAULT_COLOR,
+ ASS_DEFAULT_BACK_COLOR,
+ ASS_DEFAULT_BOLD,
+ ASS_DEFAULT_ITALIC,
+ ASS_DEFAULT_UNDERLINE,
+ ASS_DEFAULT_ALIGNMENT);
+}
+
 void ff_ass_init(AVSubtitle *sub)
 {
  memset(sub, 0, sizeof(*sub));

libavcodec/ass.h

@@ -24,6 +24,51 @@
 
 #include "avcodec.h"
 
+/**
+ * Default values for ASS style.
+ * @defgroup ass_default
+ * @{
+ */
+#define ASS_DEFAULT_FONT "Arial"
+#define ASS_DEFAULT_FONT_SIZE 16
+#define ASS_DEFAULT_COLOR 0xffffff
+#define ASS_DEFAULT_BACK_COLOR 0
+#define ASS_DEFAULT_BOLD 0
+#define ASS_DEFAULT_ITALIC 0
+#define ASS_DEFAULT_UNDERLINE 0
+#define ASS_DEFAULT_ALIGNMENT 2
+/** @} */
+
+/**
+ * Generate a suitable AVCodecContext.subtitle_header for SUBTITLE_ASS.
+ *
+ * @param avctx pointer to the AVCodecContext
+ * @param font name of the default font face to use
+ * @param font_size default font size to use
+ * @param color default text color to use (ABGR)
+ * @param back_color default background color to use (ABGR)
+ * @param bold 1 for bold text, 0 for normal text
+ * @param italic 1 for italic text, 0 for normal text
+ * @param underline 1 for underline text, 0 for normal text
+ * @param alignment position of the text (left, center, top...), defined after
+ * the layout of the numpad (1-3 sub, 4-6 mid, 7-9 top)
+ * @return >= 0 on success otherwise an error code <0
+ */
+int ff_ass_subtitle_header(AVCodecContext *avctx,
+ const char *font, int font_size,
+ int color, int back_color,
+ int bold, int italic, int underline,
+ int alignment);
+
+/**
+ * Generate a suitable AVCodecContext.subtitle_header for SUBTITLE_ASS
+ * with default style.
+ *
+ * @param avctx pointer to the AVCodecContext
+ * @return >= 0 on success otherwise an error code <0
+ */
+int ff_ass_subtitle_header_default(AVCodecContext *avctx);
+
 /**
  * Initialize an AVSubtitle structure for use with ff_ass_add_rect().
  *

libavcodec/avcodec.h

@@ -32,8 +32,8 @@
 #include "libavutil/cpu.h"
 
 #define LIBAVCODEC_VERSION_MAJOR 52
-#define LIBAVCODEC_VERSION_MINOR 100
-#define LIBAVCODEC_VERSION_MICRO 1
+#define LIBAVCODEC_VERSION_MINOR 101
+#define LIBAVCODEC_VERSION_MICRO 0
 
 #define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
  LIBAVCODEC_VERSION_MINOR, \

libavcodec/srtdec.c

@@ -0,0 +1,240 @@
+/*
+ * SubRip subtitle decoder
+ * Copyright (c) 2010 Aurelien Jacobs <[email protected]>
+ *
+ * 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 "libavutil/avstring.h"
+#include "libavcore/parseutils.h"
+#include "avcodec.h"
+#include "ass.h"
+
+static int html_color_parse(AVCodecContext *avctx, const char *str)
+{
+ uint8_t rgba[4];
+ if (av_parse_color(rgba, str, strcspn(str, "\" >"), avctx) < 0)
+ return -1;
+ return rgba[0] | rgba[1] << 8 | rgba[2] << 16;
+}
+
+enum {
+ PARAM_UNKNOWN = -1,
+ PARAM_SIZE,
+ PARAM_COLOR,
+ PARAM_FACE,
+ PARAM_NUMBER
+};
+
+typedef struct {
+ char tag[128];
+ char param[PARAM_NUMBER][128];
+} SrtStack;
+
+static const char *srt_to_ass(AVCodecContext *avctx, char *out, char *out_end,
+ const char *in, int x1, int y1, int x2, int y2)
+{
+ char c, *param, buffer[128], tmp[128];
+ int len, tag_close, sptr = 1, line_start = 1, an = 0, end = 0;
+ SrtStack stack[16];
+
+ stack[0].tag[0] = 0;
+ strcpy(stack[0].param[PARAM_SIZE], "{\\fs}");
+ strcpy(stack[0].param[PARAM_COLOR], "{\\c}");
+ strcpy(stack[0].param[PARAM_FACE], "{\\fn}");
+
+ if (x1 >= 0 && y1 >= 0) {
+ if (x2 >= 0 && y2 >= 0 && (x2 != x1 || y2 != y1))
+ out += snprintf(out, out_end-out,
+ "{\\an1}{\\move(%d,%d,%d,%d)}", x1, y1, x2, y2);
+ else
+ out += snprintf(out, out_end-out, "{\\an1}{\\pos(%d,%d)}", x1, y1);
+ }
+
+ for (; *in && out < out_end && !end; in++) {
+ switch (*in) {
+ case '\r':
+ break;
+ case '\n':
+ if (line_start) {
+ end = 1;
+ break;
+ }
+ while (out[-1] == ' ')
+ out--;
+ out += snprintf(out, out_end-out, "\\N");
+ line_start = 1;
+ break;
+ case ' ':
+ if (!line_start)
+ *out++ = *in;
+ break;
+ case '{': /* skip all {\xxx} substrings except for {\an%d}
+ and all microdvd like styles such as {Y:xxx} */
+ an += sscanf(in, "{\\an%*1u}%c", &c) == 1;
+ if ((an != 1 && sscanf(in, "{\\%*[^}]}%n%c", &len, &c) > 0) ||
+ sscanf(in, "{%*1[CcFfoPSsYy]:%*[^}]}%n%c", &len, &c) > 0) {
+ in += len - 1;
+ } else
+ *out++ = *in;
+ break;
+ case '<':
+ tag_close = in[1] == '/';
+ if (sscanf(in+tag_close+1, "%128[^>]>%n%c", buffer, &len,&c) >= 2) {
+ if ((param = strchr(buffer, ' ')))
+ *param++ = 0;
+ if ((!tag_close && sptr < FF_ARRAY_ELEMS(stack)) ||
+ ( tag_close && sptr > 0 && !strcmp(stack[sptr-1].tag, buffer))) {
+ int i, j, unknown = 0;
+ in += len + tag_close;
+ if (!tag_close)
+ memset(stack+sptr, 0, sizeof(*stack));
+ if (!strcmp(buffer, "font")) {
+ if (tag_close) {
+ for (i=PARAM_NUMBER-1; i>=0; i--)
+ if (stack[sptr-1].param[i][0])
+ for (j=sptr-2; j>=0; j--)
+ if (stack[j].param[i][0]) {
+ out += snprintf(out, out_end-out,
+ stack[j].param[i]);
+ break;
+ }
+ } else {
+ while (param) {
+ if (!strncmp(param, "size=", 5)) {
+ unsigned font_size;
+ param += 5 + (param[5] == '"');
+ if (sscanf(param, "%u", &font_size) == 1) {
+ snprintf(stack[sptr].param[PARAM_SIZE],
+ sizeof(stack[0].param[PARAM_SIZE]),
+ "{\\fs%u}", font_size);
+ }
+ } else if (!strncmp(param, "color=", 6)) {
+ param += 6 + (param[6] == '"');
+ snprintf(stack[sptr].param[PARAM_COLOR],
+ sizeof(stack[0].param[PARAM_COLOR]),
+ "{\\c&H%X&}",
+ html_color_parse(avctx, param));
+ } else if (!strncmp(param, "face=", 5)) {
+ param += 5 + (param[5] == '"');
+ len = strcspn(param,
+ param[-1] == '"' ? "\"" :" ");
+ av_strlcpy(tmp, param,
+ FFMIN(sizeof(tmp), len+1));
+ param += len;
+ snprintf(stack[sptr].param[PARAM_FACE],
+ sizeof(stack[0].param[PARAM_FACE]),
+ "{\\fn%s}", tmp);
+ }
+ if ((param = strchr(param, ' ')))
+ param++;
+ }
+ for (i=0; i<PARAM_NUMBER; i++)
+ if (stack[sptr].param[i][0])
+ out += snprintf(out, out_end-out,
+ stack[sptr].param[i]);
+ }
+ } else if (!buffer[1] && strspn(buffer, "bisu") == 1) {
+ out += snprintf(out, out_end-out,
+ "{\\%c%d}", buffer[0], !tag_close);
+ } else {
+ unknown = 1;
+ snprintf(tmp, sizeof(tmp), "</%s>", buffer);
+ }
+ if (tag_close) {
+ sptr--;
+ } else if (unknown && !strstr(in, tmp)) {
+ in -= len + tag_close;
+ *out++ = *in;
+ } else
+ av_strlcpy(stack[sptr++].tag, buffer,
+ sizeof(stack[0].tag));
+ break;
+ }
+ }
+ default:
+ *out++ = *in;
+ break;
+ }
+ if (*in != ' ' && *in != '\r' && *in != '\n')
+ line_start = 0;
+ }
+
+ out = FFMIN(out, out_end-3);
+ while (!strncmp(out-2, "\\N", 2))
+ out -= 2;
+ while (out[-1] == ' ')
+ out--;
+ out += snprintf(out, out_end-out, "\r\n");
+ return in;
+}
+
+static const char *read_ts(const char *buf, int *ts_start, int *ts_end,
+ int *x1, int *y1, int *x2, int *y2)
+{
+ int i, hs, ms, ss, he, me, se;
+
+ for (i=0; i<2; i++) {
+ /* try to read timestamps in either the first or second line */
+ int c = sscanf(buf, "%d:%2d:%2d%*1[,.]%3d --> %d:%2d:%2d%*1[,.]%3d"
+ "%*[ ]X1:%u X2:%u Y1:%u Y2:%u",
+ &hs, &ms, &ss, ts_start, &he, &me, &se, ts_end,
+ x1, x2, y1, y2);
+ buf += strcspn(buf, "\n") + 1;
+ if (c >= 8) {
+ *ts_start = 100*(ss + 60*(ms + 60*hs)) + *ts_start/10;
+ *ts_end = 100*(se + 60*(me + 60*he)) + *ts_end /10;
+ return buf;
+ }
+ }
+ return NULL;
+}
+
+static int srt_decode_frame(AVCodecContext *avctx,
+ void *data, int *got_sub_ptr, AVPacket *avpkt)
+{
+ AVSubtitle *sub = data;
+ int ts_start, ts_end, x1 = -1, y1 = -1, x2 = -1, y2 = -1;
+ char buffer[2048];
+ const char *ptr = avpkt->data;
+
+ if (avpkt->size <= 0)
+ return avpkt->size;
+
+ ff_ass_init(sub);
+
+ while (*ptr) {
+ ptr = read_ts(ptr, &ts_start, &ts_end, &x1, &y1, &x2, &y2);
+ if (!ptr)
+ break;
+ ptr = srt_to_ass(avctx, buffer, buffer+sizeof(buffer), ptr,
+ x1, y1, x2, y2);
+ ff_ass_add_rect(sub, buffer, ts_start, ts_end, 0);
+ }
+
+ *got_sub_ptr = sub->num_rects > 0;
+ return avpkt->size;
+}
+
+AVCodec srt_decoder = {
+ .name = "srt",
+ .long_name = NULL_IF_CONFIG_SMALL("SubRip subtitle"),
+ .type = AVMEDIA_TYPE_SUBTITLE,
+ .id = CODEC_ID_SRT,
+ .init = ff_ass_subtitle_header_default,
+ .decode = srt_decode_frame,
+};