[FFmpeg-cvslog] avfilter/vf_tinterlace: Fix vf_tinterlace mode 6 (interlacex2)

[Jasper Taylor]

ffmpeg | branch: master | Jasper Taylor <jasper at simulistics.com> | Sun Mar 16 15:29:30 2014 +0000| [0d5ae023b2b7b860cbbfb7763f94da76bc841788] | committer: Michael Niedermayer

avfilter/vf_tinterlace: Fix vf_tinterlace mode 6 (interlacex2)

The purpose of this filter mode is to allow interlaced content to
display properly in interlaced video modes, as described in
http://forum.xbmc.org/showthread.php?tid=81834 and
https://github.com/mpv-player/mpv/issues/624#issuecomment-37685195 . The
filter doubles the video frame rate, but does not work properly because:
(1) it does not set the properties of the output stream to indicate the
doubled frame rate, and
(2) it does not set an appropriate PTS on the extra frames.
The attached patch fixes these problems by settling these values the
same way they are set in vf_yadif mode 1 (field) which also doubles the
frame rate.

Signed-off-by: Michael Niedermayer <michaelni at gmx.at>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=0d5ae023b2b7b860cbbfb7763f94da76bc841788
---

 libavfilter/vf_tinterlace.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/libavfilter/vf_tinterlace.c b/libavfilter/vf_tinterlace.c
index db82393..3ebb971 100644
--- a/libavfilter/vf_tinterlace.c
+++ b/libavfilter/vf_tinterlace.c
@@ -145,6 +145,12 @@ static int config_out_props(AVFilterLink *outlink)
                 tinterlace->mode);
         tinterlace->flags &= ~TINTERLACE_FLAG_VLPF;
     }
+    if (tinterlace->mode == MODE_INTERLACEX2) {
+        outlink->time_base.num = inlink->time_base.num;
+        outlink->time_base.den = inlink->time_base.den * 2;
+        outlink->frame_rate = av_mul_q(inlink->frame_rate, (AVRational){2,1});
+    }
+
     av_log(ctx, AV_LOG_VERBOSE, "mode:%d filter:%s h:%d -> h:%d\n",
            tinterlace->mode, (tinterlace->flags & TINTERLACE_FLAG_VLPF) ? "on" : "off",
            inlink->h, outlink->h);
@@ -321,6 +327,8 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
         if (!out)
             return AVERROR(ENOMEM);
         out->interlaced_frame = 1;
+        if (cur->pts != AV_NOPTS_VALUE)
+            out->pts = cur->pts*2;
 
         if ((ret = ff_filter_frame(outlink, out)) < 0)
             return ret;
@@ -333,6 +341,10 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
         av_frame_copy_props(out, next);
         out->interlaced_frame = 1;
 
+        if (next->pts != AV_NOPTS_VALUE && cur->pts != AV_NOPTS_VALUE)
+            out->pts = cur->pts + next->pts;
+        else
+            out->pts = AV_NOPTS_VALUE;
         /* write current frame second field lines into the second field of the new frame */
         copy_picture_field(out->data, out->linesize,
                            (const uint8_t **)cur->data, cur->linesize,