From d9f72e53bfe76b5c40bb444f0a81617dffdfedf4 Mon Sep 17 00:00:00 2001 From: Marton Balint Date: Sat, 28 Apr 2018 21:42:34 +0200 Subject: [PATCH] avcodec/libzvbi-teletextdec: add support for selecting subtitle pages only Signed-off-by: Marton Balint --- doc/decoders.texi | 5 +++-- libavcodec/libzvbi-teletextdec.c | 33 ++++++++++++++++++++++---------- libavcodec/version.h | 2 +- 3 files changed, 27 insertions(+), 13 deletions(-) diff --git a/doc/decoders.texi b/doc/decoders.texi index a551d5d0fd..8f07bc1afb 100644 --- a/doc/decoders.texi +++ b/doc/decoders.texi @@ -248,8 +248,9 @@ configuration. You need to explicitly configure the build with @table @option @item txt_page -List of teletext page numbers to decode. You may use the special * string to -match all pages. Pages that do not match the specified list are dropped. +List of teletext page numbers to decode. Pages that do not match the specified +list are dropped. You may use the special @code{*} string to match all pages, +or @code{subtitle} to match all subtitle pages. Default value is *. @item txt_chop_top Discards the top teletext line. Default value is 1. diff --git a/libavcodec/libzvbi-teletextdec.c b/libavcodec/libzvbi-teletextdec.c index a800ad34ae..ccded23e7c 100644 --- a/libavcodec/libzvbi-teletextdec.c +++ b/libavcodec/libzvbi-teletextdec.c @@ -73,6 +73,7 @@ typedef struct TeletextContext vbi_sliced sliced[MAX_SLICES]; int readorder; + uint8_t subtitle_map[2048]; } TeletextContext; static int chop_spaces_utf8(const unsigned char* t, int len) @@ -281,16 +282,14 @@ static void handler(vbi_event *ev, void *user_data) vbi_page page; int res; char pgno_str[12]; - vbi_subno subno; - vbi_page_type vpt; int chop_top; - char *lang; + int is_subtitle_page = ctx->subtitle_map[ev->ev.ttx_page.pgno & 0x7ff]; snprintf(pgno_str, sizeof pgno_str, "%03x", ev->ev.ttx_page.pgno); av_log(ctx, AV_LOG_DEBUG, "decoded page %s.%02x\n", pgno_str, ev->ev.ttx_page.subno & 0xFF); - if (strcmp(ctx->pgno, "*") && !strstr(ctx->pgno, pgno_str)) + if (strcmp(ctx->pgno, "*") && (strcmp(ctx->pgno, "subtitle") || !is_subtitle_page) && !strstr(ctx->pgno, pgno_str)) return; if (ctx->handler_ret < 0) return; @@ -303,9 +302,7 @@ static void handler(vbi_event *ev, void *user_data) if (!res) return; - vpt = vbi_classify_page(ctx->vbi, ev->ev.ttx_page.pgno, &subno, &lang); - chop_top = ctx->chop_top || - ((page.rows > 1) && (vpt == VBI_SUBTITLE_PAGE)); + chop_top = ctx->chop_top || ((page.rows > 1) && is_subtitle_page); av_log(ctx, AV_LOG_DEBUG, "%d x %d page chop:%d\n", page.columns, page.rows, chop_top); @@ -357,11 +354,26 @@ static int slice_to_vbi_lines(TeletextContext *ctx, uint8_t* buf, int size) else { int line_offset = buf[2] & 0x1f; int field_parity = buf[2] & 0x20; - int i; + uint8_t *p = ctx->sliced[lines].data; + int i, pmag; ctx->sliced[lines].id = VBI_SLICED_TELETEXT_B; ctx->sliced[lines].line = (line_offset > 0 ? (line_offset + (field_parity ? 0 : 313)) : 0); for (i = 0; i < 42; i++) - ctx->sliced[lines].data[i] = vbi_rev8(buf[4 + i]); + p[i] = vbi_rev8(buf[4 + i]); + /* Unfortunately libzvbi does not expose page flags, and + * vbi_classify_page only checks MIP, so we have to manually + * decode the page flags and store the results. */ + pmag = vbi_unham16p(p); + if (pmag >= 0 && pmag >> 3 == 0) { // We found a row 0 header + int page = vbi_unham16p(p + 2); + int flags1 = vbi_unham16p(p + 6); + int flags2 = vbi_unham16p(p + 8); + if (page >= 0 && flags1 >= 0 && flags2 >= 0) { + int pgno = ((pmag & 7) << 8) + page; + // Check for disabled NEWSFLASH flag and enabled SUBTITLE and SUPRESS_HEADER flags + ctx->subtitle_map[pgno] = (!(flags1 & 0x40) && flags1 & 0x80 && flags2 & 0x01); + } + } lines++; } } @@ -502,6 +514,7 @@ static int teletext_close_decoder(AVCodecContext *avctx) vbi_decoder_delete(ctx->vbi); ctx->vbi = NULL; ctx->pts = AV_NOPTS_VALUE; + memset(ctx->subtitle_map, 0, sizeof(ctx->subtitle_map)); if (!(avctx->flags2 & AV_CODEC_FLAG2_RO_FLUSH_NOOP)) ctx->readorder = 0; return 0; @@ -515,7 +528,7 @@ static void teletext_flush(AVCodecContext *avctx) #define OFFSET(x) offsetof(TeletextContext, x) #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM static const AVOption options[] = { - {"txt_page", "list of teletext page numbers to decode, * is all", OFFSET(pgno), AV_OPT_TYPE_STRING, {.str = "*"}, 0, 0, SD}, + {"txt_page", "page numbers to decode, subtitle for subtitles, * for all", OFFSET(pgno), AV_OPT_TYPE_STRING, {.str = "*"}, 0, 0, SD}, {"txt_chop_top", "discards the top teletext line", OFFSET(chop_top), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, SD}, {"txt_format", "format of the subtitles (bitmap or text)", OFFSET(format_id), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD, "txt_format"}, {"bitmap", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = 0}, 0, 0, SD, "txt_format"}, diff --git a/libavcodec/version.h b/libavcodec/version.h index b9752ce62c..5e71b48816 100644 --- a/libavcodec/version.h +++ b/libavcodec/version.h @@ -29,7 +29,7 @@ #define LIBAVCODEC_VERSION_MAJOR 58 #define LIBAVCODEC_VERSION_MINOR 20 -#define LIBAVCODEC_VERSION_MICRO 100 +#define LIBAVCODEC_VERSION_MICRO 101 #define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \ LIBAVCODEC_VERSION_MINOR, \