Serviio

ffmpeg transcoded .ts files with an incorrect frame rate

Media Info


ffmpeg


Serviio PRO 1.5.1
Ubuntu 14.04


ffmpeg

Can you post ffmpeg -i for the file?

compi

Seriio uses the tbr field (when available) to get the frame rate. According to his, it's the most reliable: http://stackoverflow.com/questions/9399 ... p-prop-fps

file is interlaced so frame rate doubles

yeah, I thought so, but I don't think I can say that from the ffmpeg output

it is possible to transcode hard in to 25fps?

Could you post your .ts file? You could use tsmuxer to cut the first 20 seconds from it to make that smaller.

I ask because I think there are problems with serviio handling interlaced files but yours appears different with a tbr = 2x fps and I need it to test further.

Further to my last post...

I'd like to know where this file came from because 2 things about it are strange.
(1) the tbr of 50 when fps is 25 and (2) the mediainfo scan type showing "interlaced".

In my experience the 50 tbr only occurs when a file has been transcoded to 50 fps, and mediainfo only displays scan type "MDAFF" when an AVC video file is interlaced. So why is this file different?

I have done further testing and cannot replicate the posted output so I would like to test the actual file, and know how it was created (direct capture, download, transcode etc).

Then I will be able to comment more on the Serviio transcoding and the ability/impact of hard transcode to 25 fps.

the file to record with vdr and then cut with ts doctor .

I'll upload the file straight up and then send a PM .

compi

Great. vrd?? Did you mean dvr? Which dvr do you use?

I am still working on this, but I cannot find a Serviio profile that would have generated the transcoding command you have posted in particular the 8000k limit. What device profile were you using?

@zip Do you add an upper mpeg2video limit when the source file exceeds -b:V 8000K. This source is -b:V 17200K.

I modified the Samsung profile . I have limited the bandwidth to 8000

<Profile id="kirch" name="(Kirchner)" extendsProfileId="1">
<ContentDirectoryMessageBuilder>org.serviio.upnp.service.contentdirectory.SamsungDLNAMessageBuilder</ContentDirectoryMessageBuilder>
<ResourceTransportProtocolHandler>org.serviio.upnp.protocol.http.transport.SamsungWiseLinkProtocolHandler</ResourceTransportProtocolHandler>
<Detection>
<UPnPSearch>
<FriendlyName>(^\[TV\][A-Z]{2}\d{2}(E|F)[A-Z]?\d{3,4}.*)|^\[TV\] Samsung</FriendlyName>
<ModelNumber>(1\.0)|(AllShare1\.0)</ModelNumber>
</UPnPSearch>
<HttpHeaders>
<!-- for BD players -->
<User-Agent>(.*SEC_HHP_BD-[EF].*)|(.*SEC_HHP_\[(HT|BD)\][EF].*)</User-Agent>
</HttpHeaders>
</Detection>
<DeviceDescription>
<ExtraElements>
&lt;sec:ProductCap&gt;smi,DCM10,getMediaInfo.sec,getCaptionInfo.sec&lt;/sec:ProductCap&gt;
&lt;sec:X_ProductCap&gt;smi,DCM10,getMediaInfo.sec,getCaptionInfo.sec&lt;/sec:X_ProductCap&gt;
</ExtraElements>
</DeviceDescription>
<MediaFormatProfiles>
<MediaFormatProfile mime-type="video/x-mkv">MATROSKA</MediaFormatProfile>
<MediaFormatProfile mime-type="video/x-msvideo" name="">AVI</MediaFormatProfile>
<MediaFormatProfile mime-type="audio/x-flac">FLAC</MediaFormatProfile>
</MediaFormatProfiles>
<ContentDirectoryDefinitionFilter>org.serviio.upnp.service.contentdirectory.definition.SamsungContentDirectoryDefinitionFilter</ContentDirectoryDefinitionFilter>
<H264LevelCheck>FILE_ATTRIBUTES</H264LevelCheck>
<Transcoding>
<!-- Transcode all videos with MPEG2VIDEO and ac3 audio transcoding -->
<Video targetContainer="mpegts" targetVCodec="mpeg2video" maxVBitrate="8000" targetACodec="ac3" aBitrate="192" forceInheritance="true">

<Matches container="*" />
</Video>
<Audio targetContainer="lpcm" forceInheritance="true">
<Matches container="mp4" />
<Matches container="ogg" />
<Matches container="adts" />
<Matches container="mp2" />
<Matches container="wavpack" />
<Matches container="mpc" />
<Matches container="ape" />
<Matches container="asf" />
</Audio>
</Transcoding>
<OnlineTranscoding>
<Video targetContainer="mpegts" maxVBitrate="8000" targetACodec="ac3" aBitrate="384">
<Matches container="applehttp" vCodec="h264"/>
</Video>
<Video targetContainer="mpegts" targetVCodec="mpeg2video" maxVBitrate="8000" targetACodec="ac3" aBitrate="384">
<Matches container="asf" /> <!-- mms -->
<Matches container="flv" /> <!-- transcoding all flv streams, even h264, to avoild premature disconnects, to avoid this, use Samsung C/D profile -->
</Video>
</OnlineTranscoding>
<AutomaticImageRotation>true</AutomaticImageRotation>
<LimitImageResolution>false</LimitImageResolution>
<Subtitles>
<SoftSubs mime-type="smi/caption" />
</Subtitles>
<ThumbnailsResolution>HD</ThumbnailsResolution>
</Profile>

To summarize, I was interested in this post because I had not seen differing fps and tbr values from ffmpeg; questioned the use of -r 50 in the ffmpeg command; and could not find the use of maxVbitrate=8000 in any Serviio profile.

Here are the results of my analysis:

1) The "25fps,50tbr" ffmpeg result is correct and indicates the file "The Walking Dead - S05E14 Falsches Licht.ts" which was captured from a TV broadcast is a 25fps h264 Progressive Segmented File (PsF).

PsF means an original 25fps progressive frame has been encoded as "interlaced" and the 2 fields in each 25 fps frame contain the even and odd lines of the original "progressive" frame but both fields have the same time stamp rather than the 1/25sec difference in field timestamps that normal interlaced fields would have . The h264 specs D.9.2 provide for this - "When clockTimestamp is equal for two fields of opposite parity that are consecutive in output order, both with ct_type equal to 0 (progressive) or ct_type equal to 2 (unknown),the two fields are indicated to have come from the same original progressive frame."
These PsF files are created at the source by the cameras and are used by broadcasters to transmit "progressive" material over systems built to work with "interlaced", in this case the TV broadcast captured by vdr (http://www.tvdr.de). (See http://wolfcrow.com/blog/understanding- ... rames-psf/)

FFmpeg recognizes h264 PsF files by showing the tbr as twice the fps eg: "25 fps, 50 tbr"
(http://forum.videohelp.com/threads/3523 ... l-in-h-264). FFMPEG will also transcode the file by default at 25fps which shows it uses its fps value rather than the tbr value.

Note that I have found no way to create these PsF files with software. The X264 encoder option "fake-interlaced" will create interlaced flagged files for authoring Blu-ray disks with 25p and 29.97p material however they contain the original progressive frames rather than the 2 interlaced fields, and ffmpeg will report them with equal fps and tbr values. (http://www.x264bluray.com/home/1080i-p)

2) The use of tbr and -r 50 by Serviio is incorrect.

As Zip has indicated above, Serviio uses "tbr" to determine the correct frame rate. Hence the ffmpeg command generated from the custom profile above contains -r 50 which results in a transcode to a 50 fps,50 tbr progressive video. Analysis shows each progressive frame consists of the interweaved odd and even field lines, and every second frame is duplicated. This shows that ffmpeg recognizes the file as 25 fps interlaced, and duplicates each 25fps frame in order to get the output frame rate to 50fps. Similarly by removing the -r 50 and letting ffmpeg default to the existing timestamps, produces a 25fps, 25 tbr progressive video. These both show the use of tbr is incorrect, and that ffmpeg itself uses the fps value.

Note that Zips justification for using tbr is from a post using 2011 fmpeg on "network camera" video. I would also refer to a 2010 post https://forums.creativecow.net/thread/291/140 which also suggests tbr is the most accurate but also suggests "You can always just exclude the -r flag and the frame rates will pass from source to destination". Given the changes to ffmpeg over the past few years including the PsF support added in 2013, and the current ffmpeg action to correctly default to the fps value, I have opened a ticket suggesting that Serviio never force the output frame rate, but rather let ffmpeg default to the existing input timestamps.

3) The use of a custom profile by the poster to transcode his files to maxVbitrate=8000K mpeg2video seems unwarranted since I have verified the Samsung will play the original avc codec without delay and without the quality loss of transcoding.

Great write-up. I will look at the ticket for a future release, thanks.

Interesting stuff. Learned a lot from it. Thanks:)

thanks it works with ver. 1.6


compi

Gesendet von meinem Xperia Z Ultra mit Tapatalk

??? What works with 1.6??