Cool. A couple of suggestions:
-crf 18 the output video will be pretty damned close to the original in quality, with a decent chunk of compression.-c:a copy you can keep the original 5.1 audio without ffmpeg having to transcode it, and therefore no loss in quality.Plex is intelligent enough to transcode only the audio if required for a device that doesn’t support DTS. The CPU hit is minimal.
@ntrevena said:
Cool. A couple of suggestions:
- If you use the
-crf 18the output video will be pretty damned close to the original in quality, with a decent chunk of compression.- If you use
-c:a copyyou can keep the original 5.1 audio without ffmpeg having to transcode it, and therefore no loss in quality.Plex is intelligent enough to transcode only the audio if required for a device that doesn’t support DTS. The CPU hit is minimal.
I used 25, and at that setting, it looks like it might take a couple hours. 18… that might be a long long time.
Interestingly, Plex does not convert just the audio on my Roku with 7.1… there is just silence on the speakers.
@wesman said:
I used 25, and at that setting, it looks like it might take a couple hours. 18… that might be a long long time.
Understood.
You can use a preset of fast; veryfast or ultrafast if time is a concern. You just won’t get the same compression ratio.
@wesman said:
Interestingly, Plex does not convert just the audio on my Roku with 7.1… there is just silence on the speakers.
How odd. It’ll do the audio transcode on my phone or Smart TV.
I wonder if that’s specific to the Roku…
@ntrevena said:
@wesman said:
I used 25, and at that setting, it looks like it might take a couple hours. 18… that might be a long long time.Understood.
You can use a preset of fast; veryfast or ultrafast if time is a concern. You just won’t get the same compression ratio.
@wesman said:
Interestingly, Plex does not convert just the audio on my Roku with 7.1… there is just silence on the speakers.How odd. It’ll do the audio transcode on my phone or Smart TV.
I wonder if that’s specific to the Roku…
Yeah, I pick slow on deliberately, the server has nothing better to do at the moment.
I think it’s a roku issue
Yes, a Roku-ism. Raise that in the Roku forum. There’s work going on now for the next update. Maybe it’s already been fixed.
@ChuckPa said:
Yes, a Roku-ism. Raise that in the Roku forum. There’s work going on now for the next update. Maybe it’s already been fixed.
I hope so, as of now, its not fixed. hopefully soon… looking at the forums… it’s been an issue for about 2 years now.
@wesman said:
@ChuckPa said:
Yes, a Roku-ism. Raise that in the Roku forum. There’s work going on now for the next update. Maybe it’s already been fixed.I hope so, as of now, its not fixed. hopefully soon… looking at the forums… it’s been an issue for about 2 years now.
not to hijack, a 7.1 audio passthrough issue? If so, that’s an issue of whatever the HDMI is plugged in to. (we all beat that to death in discussions)
@ChuckPa said:
not to hijack, a 7.1 audio passthrough issue? If so, that’s an issue of whatever the HDMI is plugged in to. (we all beat that to death in discussions)
I don’t understand, the Roku 4 is plugged into a Yamaha RX-A1060 (basically top of the line) what do you mean “whatever the hdmi is plug into”?
I … think … I must have done something wrong… This compression ration seems unrealistic to maintain the same quality level.
I’ll have to get back to that in a bit, though, got to get the kids
From the Dev.
Here’s the real nuance. The audio can be DTS-HD 7.1, but the metadata has to state 6ch (the core) for it to work.
The dev has been pushing. Perhaps you all can help push them too. It’s been this way for a while and really broken on the newer/bigger models.
I did see the workaround, however, using it causes the rear two speakers (channels 7 and 8) to just stop working. which is unacceptable.
A 5.1 audio will repeat the surrounds to the rear, which is preferable to having no sound in the rear. HOPEFULLY Roku will fix this issue. its truly ridiculous.
@wesman said:
I … think … I must have done something wrong… This compression ration seems unrealistic to maintain the same quality level.
I’ll have to get back to that in a bit, though, got to get the kids
https://forums.plex.tv/discussion/comment/1281647/#Comment_1281647
Essentially, you’ve taken a raw (not quite, but close enough) video, and compressed it for the first time. You will always see this kind of compression on the first run.
If you don’t believe it’s good enough, fire up VLC and compare the two side by side.
Remember, it’s not about actual loss, but perceived loss. Throw it into Plex, and see what it looks/sounds like on your TV/AV.
@ntrevena said:
@wesman said:
I … think … I must have done something wrong… This compression ration seems unrealistic to maintain the same quality level.
I’ll have to get back to that in a bit, though, got to get the kidshttps://forums.plex.tv/discussion/comment/1281647/#Comment_1281647
Essentially, you’ve taken a raw (not quite, but close enough) video, and compressed it for the first time. You will always see this kind of compression on the first run.
If you don’t believe it’s good enough, fire up VLC and compare the two side by side.
Remember, it’s not about actual loss, but perceived loss. Throw it into Plex, and see what it looks/sounds like on your TV/AV.
going to do that later tonight, I am going to play it in my media room, that baby’s got 165 inches of pure 1080P Heaven.. We’ll see how well it performs.
@wesman said:
going to do that later tonight, I am going to play it in my media room, that baby’s got 165 inches of pure 1080P Heaven… We’ll see how well it performs.
Fair enough. I look forward to hearing how it goes.
Wagers a bet that it won’t hold a candle to 50+ Mbps 1080p but wonders how many yards back you have to sit to watch it
(can you tell I’m jealous? 
)
@ChuckPa said:
Wagers a bet that it won’t hold a candle to 50+ Mbps 1080p but wonders how many yards back you have to sit to watch it(can you tell I’m jealous?
)
Haha! I would say it too, but you’d be surprised at how far the compression has come over the last 10 years.
I only heavily encode video I don’t care about. You know, the TV Series you can live without, or the shows your wife watches etc… I mean I wouldn’t do that to my wife, but just as an example of something someone might do…
Houston, we have a problem
Well @ntrevena and @ChuckPa , I went to play it, and noticed immediately that it was transcoding BOTH Audio and Video.
So, I jumped into the Roku’s settings a saw the following.
But it should be Direct Playing
Transcoding the Audio too for some reason.. I think the Roku 4 supports both AAC and HEVC, right?
I did attach the log incase someone knows how to read that.
Here’s the important parts:
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: analyzing media item 100526
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: Oblivion (2013): Direct Play is disabled
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: Oblivion (2013): media must be transcoded in order to use the hls protocol
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: Oblivion (2013): no direct play video profile exists for http/mkv/hevc
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: Oblivion (2013): no direct play video profile exists for http/mkv/hevc/aac
Oct 19, 2016 09:07:00.592 [2108] DEBUG - Oblivion - audio.channels limitation applies: 6 > 2
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: Oblivion (2013): no remuxable profile found, so video stream will be transcoded
Oct 19, 2016 09:07:00.592 [2108] DEBUG - MDE: computed resolution bounding box of 1920x1080.
Oct 19, 2016 09:07:00.592 [2108] DEBUG - Scaled up video bitrate to 18513Kbps based on 4.500000x fudge factor.
Oct 19, 2016 09:07:00.592 [2108] DEBUG - Oblivion - audio.channels limitation applies: 6 > 2
Oct 19, 2016 09:07:00.608 [2108] DEBUG - Oblivion - audio.channels limitation applies: 6 > 2
Oct 19, 2016 09:07:00.608 [2108] DEBUG - MDE: Oblivion (2013): selected media 0 / 100526
Oct 19, 2016 09:07:00.608 [2108] DEBUG - Streaming Resource: Adding session 0BBFF3C8:PlexYY001D808908 which is using transcoder slot. Used slots is now 1
Oct 19, 2016 09:07:00.608 [2108] DEBUG - Streaming Resource: Added session 0BBFF3C8:PlexYY001D808908
The Roku 4 is not responding as supporting MKV. Your Screenshot also shows HLS is set.
Video had to be transcoded to get to HLS from H.264
Audio had to be transcoded because it’s 6 channel and not 2 channel.
Playing back on the Roku 3 produces this result with 33 Mbps video and 7.1 audio. Showing the before and during playback images.
