[FFmpeg-devel] [PATCH 1/1] fftools/ffmpeg: fix for all forced key frames when 'copyts' is enabled

[vdixit at akamai.com]

From: Vishwanath Dixit <vdixit at akamai.com>

Forced key frames generation functionality was assuming the first PTS
value as zero, but, when 'copyts' is enabled, the first PTS can be any
big number. This was eventually forcing all the frames as key frames.
To resolve this issue, update has been made to use first input pts as
reference pts.
---
 fftools/ffmpeg.c     | 6 +++++-
 fftools/ffmpeg.h     | 1 +
 fftools/ffmpeg_opt.c | 1 +
 3 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/fftools/ffmpeg.c b/fftools/ffmpeg.c
index 5a19a09..10f3012 100644
--- a/fftools/ffmpeg.c
+++ b/fftools/ffmpeg.c
@@ -1236,8 +1236,12 @@ static void do_video_out(OutputFile *of,
         in_picture->quality = enc->global_quality;
         in_picture->pict_type = 0;
 
+        if (ost->forced_kf_ref_pts == AV_NOPTS_VALUE &&
+            in_picture->pts != AV_NOPTS_VALUE)
+            ost->forced_kf_ref_pts = in_picture->pts;
+
         pts_time = in_picture->pts != AV_NOPTS_VALUE ?
-            in_picture->pts * av_q2d(enc->time_base) : NAN;
+            (in_picture->pts - ost->forced_kf_ref_pts) * av_q2d(enc->time_base) : NAN;
         if (ost->forced_kf_index < ost->forced_kf_count &&
             in_picture->pts >= ost->forced_kf_pts[ost->forced_kf_index]) {
             ost->forced_kf_index++;
diff --git a/fftools/ffmpeg.h b/fftools/ffmpeg.h
index d44b7a5..eb1eaf6 100644
--- a/fftools/ffmpeg.h
+++ b/fftools/ffmpeg.h
@@ -484,6 +484,7 @@ typedef struct OutputStream {
     AVRational frame_aspect_ratio;
 
     /* forced key frames */
+    int64_t forced_kf_ref_pts;
     int64_t *forced_kf_pts;
     int forced_kf_count;
     int forced_kf_index;
diff --git a/fftools/ffmpeg_opt.c b/fftools/ffmpeg_opt.c
index 8ae68ae..36bce44 100644
--- a/fftools/ffmpeg_opt.c
+++ b/fftools/ffmpeg_opt.c
@@ -1324,6 +1324,7 @@ static OutputStream *new_output_stream(OptionsContext *o, AVFormatContext *oc, e
     ost->file_index = nb_output_files - 1;
     ost->index      = idx;
     ost->st         = st;
+    ost->forced_kf_ref_pts = AV_NOPTS_VALUE;
     st->codecpar->codec_type = type;
 
     ret = choose_encoder(o, oc, ost);
-- 
1.9.1