Interesting Playback Anomaly

[ftanner]

I've noticed an interesting playback anomaly that I think might be more of an ffmpeg thing, but I wanted toget your take on it.

So the player I am using for this (I haven't tested it on another one yet) is a Sony BluRay Player.

When I play a movie that has an intentionally pixelated image in it, like the dream sequence in Prometheus or some of the time viewer sequences in Deja Vu (watching these movies at 1080p), I have noticed stuttering.

This stuttering only happens during the duration of these pixelated sequences.

Have you heard of this before?

PS... I will see if I get the same result on my Samsung Smart TV.

[Paul]

We have not seen this before. My guess is it could be the way the videos were encoded.

If the video(s) are being transcoded on-the-fly by Mezzmo, then they may be being re-muxed for fast transcoding speed. This means that the video and/or audio codecs/channels in the original video are copied into the transcoded video. If you wish, you can pre-transcode the video and do a full transcode of the codecs/channels. This may eliminate any possible encoding issues in the original video. When pre-transcoding, make sure you select the 'Force full transcode of all channels' checkbox on the Pre-transcode Formats dialog. Let us know how it goes.

[ftanner]

We have not seen this before. My guess is it could be the way the videos were encoded.

If the video(s) are being transcoded on-the-fly by Mezzmo, then they may be being re-muxed for fast transcoding speed. This means that the video and/or audio codecs/channels in the original video are copied into the transcoded video. If you wish, you can pre-transcode the video and do a full transcode of the codecs/channels. This may eliminate any possible encoding issues in the original video. When pre-transcoding, make sure you select the 'Force full transcode of all channels' checkbox on the Pre-transcode Formats dialog. Let us know how it goes.

They're not being transcoded. They're being played natively.

I checked the Samsung TV. During the same sequence using the Samsung TV's SmartHub, it pauses every few seconds and displays the "loading" icon and then repeats.

[Paul]

Understand. Given Mezzmo server is streaming the file directly to your device(s), then the problem will most likely be either your home network bandwidth not being fast enough for the video, or the encoding of the video itself causing the firmware on your device(s) to have problems decoding and playing that part of the video. Right-click on the video in Mezzmo and click 'Get FFmpeg Information'. Post that here and we may see a clue as to the problem.

[ftanner]

Understand. Given Mezzmo server is streaming the file directly to your device(s), then the problem will most likely be either your home network bandwidth not being fast enough for the video, or the encoding of the video itself causing the firmware on your device(s) to have problems decoding and playing that part of the video. Right-click on the video in Mezzmo and click 'Get FFmpeg Information'. Post that here and we may see a clue as to the problem.

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At least one output file must be specified

<MEZZMO>: Child process ended with code: 109, ExitCode=1


---> DB Level Info: 41, 100
---> Frame rate: 23.98
---> Aspect ratio:
---> Duration: 02:03:46

[Paul]

The video does not have an overly high video bitrate (~3Mb/sec) so I don't think the problem is a too high video bitrate causing the stuttering. So, it does suggest the actual video's encoding may have a problem in that particular section of the video so that your device's firmware cannot decode & play that part properly. You can test this yourself by pre-transcoding the video with Mezzmo and then try playing the newly transcoded video. If it works, then it does confirm the encoding issue. To pre-transcode the video, right-click on it in Mezzmo and click 'Pre-transcode Files'. On the Pre-transcode Files dialog, select your device and click 'Choose Formats'. On the Pre-transcode Formats dialog, select the bolded format and select the 'Force full transcode of all channels' checkbox. Click OK. Select the 'Pre-transcode files even if they match the devices supported formats' checkbox and click OK. Wait until transcoding has completed and then try to stream the video again. Hopefully it plays smoothly all the way through now.

[ftanner]

The video does not have an overly high video bitrate (~3Mb/sec) so I don't think the problem is a too high video bitrate causing the stuttering. So, it does suggest the actual video's encoding may have a problem in that particular section of the video so that your device's firmware cannot decode & play that part properly. You can test this yourself by pre-transcoding the video with Mezzmo and then try playing the newly transcoded video. If it works, then it does confirm the encoding issue. To pre-transcode the video, right-click on it in Mezzmo and click 'Pre-transcode Files'. On the Pre-transcode Files dialog, select your device and click 'Choose Formats'. On the Pre-transcode Formats dialog, select the bolded format and select the 'Force full transcode of all channels' checkbox. Click OK. Select the 'Pre-transcode files even if they match the devices supported formats' checkbox and click OK. Wait until transcoding has completed and then try to stream the video again. Hopefully it plays smoothly all the way through now.

I will give that a shot and see what happens. I will let you know,

[ftanner]

The video does not have an overly high video bitrate (~3Mb/sec) so I don't think the problem is a too high video bitrate causing the stuttering. So, it does suggest the actual video's encoding may have a problem in that particular section of the video so that your device's firmware cannot decode & play that part properly. You can test this yourself by pre-transcoding the video with Mezzmo and then try playing the newly transcoded video. If it works, then it does confirm the encoding issue. To pre-transcode the video, right-click on it in Mezzmo and click 'Pre-transcode Files'. On the Pre-transcode Files dialog, select your device and click 'Choose Formats'. On the Pre-transcode Formats dialog, select the bolded format and select the 'Force full transcode of all channels' checkbox. Click OK. Select the 'Pre-transcode files even if they match the devices supported formats' checkbox and click OK. Wait until transcoding has completed and then try to stream the video again. Hopefully it plays smoothly all the way through now.

So, I did as you suggested and that seems to have worked. Thank you for your assistance.

[Paul]

OK - glad we determined that the original video had some strange encoding. Have fun streaming with Mezzmo!