On Sun, May 6, 2018 at 2:05 PM, Marton Balint <c...@passwd.hu> wrote:
> Signed-off-by: Marton Balint <c...@passwd.hu>
> ---
> doc/decoders.texi | 5 +++--
> libavcodec/libzvbi-teletextdec.c | 31 ++++++++++++++++++++++---------
> 2 files changed, 25 insertions(+), 11 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.
>
Thanks for adding this. It works as expected for me.
Might be worth documenting in the AVOption.help text as well.
Aman
> 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..56a7182882 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;
> --
> 2.13.6
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
