video artefacts when seeking

Wowza Streaming Engine
1

Hello,

we use in our intranet the Wowza Media Server for vod streaming.

With files encoded from a SDI Source (Decklink Blackmagic) everything works fine.

With Files encodec from DVB-S we have video artefacts when seeking.

It seems that the wowza-Server does not seek to next I-Frame. After a I-Frame the Video is OK

Software: Wowza Media Server 3.6.2 build5334

JW-Player 6.9.4867

ffmpeg version 2.4.git built on Sep 26 2014

example Files

https://www.dropbox.com/sh/b0tkauy9687z22s/AACAqEHHPh4A913xplFxu6_ha?dl=0#/

ffmpeg -y -i /var/ramdisk/$sender-$jahr-$monat-$tag-$stunde.mpg -nostdin -c:v libx264 -g 25 -aspect 16:9 -movflags faststart \

-crf $videodatenrate -c:a aac -ab $audiodatenrate -async 1 -strict -2 -vf crop=in_w-24:in_h-24,yadif=2:-1:0,scale=1008:568 \

-threads 0 -loglevel info /var/ramdisk/$sender-$jahr-$monat-$tag-$stunde.mp4

thank you

J.Grill

2

Hello there and welcome to the Wowza support forum.

This is usually caused by a lack of keyframes within the source file and/or bandwidth which is close to that of the stream. When seeking Wowza needs to clear the current buffer to the client before seeking, so this may take longer than expected due to bandwidth constraints, and it may not always be to a keyframe thus you can get artifacts and only when the next keyframe arrives does the picture get fully reset.

For RTMP clients you can add this Property to your application:

How to enable enhanced seeking for RTMP playback

Kind regards,

Salvadore