Is it possible to convert Transport Streams for Apple TV?

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Level 1

40 points

Is it possible to convert Transport Streams for Apple TV?

I wanted to compare how some of the high def contents show up on Apple TV. I have many high def transport streams that are used by Digital TV manufacturers to assess video quality. So, I tried to convert some of them using Handbrake. The conversion completes without any errors. But, Quicktime reports that the file is not of proper format and for the same reason, it doesn't appear under iTunes. I have used the same HB settings to convert some of my DVDs (which are of course Standard Def) into H.264 format that Apple TV wants (encoded at 2500 kbps).

Has anyone tried to do something similar to this?

Pentium, Windows XP Pro

Posted on Mar 3, 2008 12:01 PM

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Answer 1

Mar 3, 2008 12:11 PM in response to new2appletv

What sort of files are they.

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Answer 2

new2appletv Author

Level 1

40 points

Mar 3, 2008 12:36 PM in response to Winston Churchill

Hi Winston,
These are called Transport Streams. When you use a Digital TV tuner, the digital data that you get decoded from the transmission can have many multiplexed channels of data. For simple explanation, you can go here http://en.wikipedia.org/wiki/MPEGtransportstream

We have some fabulous streams that show off the beauty and clarity of digital transmission. We remodulate and upconvert these streams and feed them back in thru the antenna connector of the TV to check the performance. Since these streams are digital, we should be able to convert them into other formats.

When you record (like a DVR/PVR) off air content using the Digital TV Tuner cards/boxes you get in the shops nowadays (Cynergy, Fusion, etc.), they save the recording in "transport stream" format.

I hope this helps with the explanation and the reason why I want to do this.

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Answer 3

Chenks

Level 5

7,435 points

Mar 3, 2008 12:39 PM in response to new2appletv

you mean a .TS file.

well in theory you should be able to convert these, but there will be a quality drop no doubt.
you could try using VisualHub to convert them (it has an AppleTV preset that seems to convert anything).

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Answer 4

DonH49

Level 6

16,716 points

Mar 3, 2008 1:57 PM in response to new2appletv

if you are referring to .m2t files then yes.

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Answer 5

Mar 3, 2008 2:27 PM in response to new2appletv

Transport streams are essentially a way of transferring data over a medium where parts of the transmission might get lost, (as opposed to program streams). Broadcast uses transport streams but so do many other situations, some cameras utilise transport streams and so do many streams over the internet.

The point I am making is that simply telling us you have a transport stream doesn't tell us anything about the files that are being transmitted. It's a little like telling us you have a diesel car instead of a petrol one and wanting to know if the tyres you have just seen on ebay will fit your car.

You'll need to tell us about the type of transport streams you have and the type of compression used in them. For example video from a modern HD camera might use mpeg2 transport streams with mpeg4/10 compression codecs.

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Answer 6

Alley_Cat

Level 7

20,560 points

Mar 3, 2008 3:42 PM in response to new2appletv

Try MPEGStreamclip for Windows, free from squared5.com

It certainly handles SD .ts files from a Topfield PVR, and I can't see why it won't handle higher def ones if they're MPEG2 encodes.

AC

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Answer 7

new2appletv Author

Level 1

40 points

Mar 4, 2008 10:27 AM in response to new2appletv

I will try the other tools. The following are the details of the Video and Audio elementary streams in the .ts file I was testing (it is a recording of the 2008 Super Bowl that I did with Fusion). I used TSReaderPro to analyze the stream.

Video----------------------------------------------------------------------
Elementary Stream PID 17 (0x0011) MPEG-2 Video
MPEG Video: Bitrate 19.000 Mbps Resolution 1280 x 720p
MPEG Video: Framerate 59.94 fps Aspect Ratio 16:9 Chroma Format 4:2:0
Descriptor: Video Stream Descriptor
Multiple frame rate flag: False
Frame rate: 29.97¼
MPEG-1 only flag: False
Constrained paramter flag: True
Still picture flag: False
Descriptor: Stream Indentifier Descriptor
06 .
Descriptor: Maximum Bitrate Descriptor
Maximum bitrate: 1921300 bytes per second
Descriptor: Data Stream Alignment Descriptor
Alignment type: video access unit
Descriptor: User Private Descriptor: 0x86
e1 65 6e 67 c1 3f ff .eng.?.
Audio----------------------------------------------------------------------
Elementary Stream PID 20 (0x0014) AC-3 Audio
AC3: Bitrate 448 Kbps Sample Rate 48 KHz
AC3: Mode complete main Coding 3/2 5 L, C, R, SL, SR
AC3: Center Mix Level -3.0 dB Surround Mix Level -3.0 dB
AC3: LFE Mode On Dialogue normalization -25 dB
Descriptor: Registration Descriptor
Format identifier: 0x41432d33 (AC-3)
Descriptor: User Private Descriptor: 0x81
08 3c 05 .<.
Descriptor: ISO639 Language Descriptor
Language: eng
Audio type: undefined
Descriptor: Stream Indentifier Descriptor
90 .
Descriptor: Maximum Bitrate Descriptor
Maximum bitrate: 62950 bytes per second
----------------------------------------------------------------------

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Answer 8

Alley_Cat

Level 7

20,560 points

Mar 4, 2008 10:33 AM in response to new2appletv

You may need to downmix the audio to stereo as the only tool I know of that will convert 5.1 AC3 is the one we can't mention and it doesn't handle .ts files.

AC

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Answer 9

Alley_Cat

Level 7

20,560 points

Mar 4, 2008 10:41 AM in response to new2appletv

Bear these in mind too:

From http://www.apple.com/uk/appletv/specs.html :

Video formats supported

* H.264 and protected H.264 (from iTunes Store): up to 5 Mbps, Progressive Main Profile (CAVLC) with AAC-LC audio up to 160 Kbps (maximum resolution: 1280 by 720 pixels at 24 fps, 960 by 540 pixels at 30 fps) in .m4v, .mp4 and .mov file formats
* iTunes Store purchased video: 320 by 240 pixels, 640 by 480 pixels, 720 by 480 pixels (anamorphic) or high-definition 720p
* MPEG-4: up to 3 Mbps, Simple Profile with AAC-LC audio up to 160 Kbps (maximum resolution: 720 by 432 pixels at 30 fps) in .m4v, .mp4 and .mov file formats

Audio formats supported

* AAC (16 to 320 Kbps); protected AAC (from iTunes Store); MP3 (16 to 320 Kbps); MP3 VBR; Apple Lossless; AIFF; WAV; Dolby Digital 5.1 surround sound pass-through

Key thing being: maximum resolution: 1280 by 720 pixels at 24 fps, 960 by 540 pixels at 30 fps

In the converter software you will need to de-interlace to the 29.97/30fps rate and potentially downsize to 960x540, alternatively you could drops the framerate to 24fps but that's not ideal.

AC

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Answer 10

new2appletv Author

Level 1

40 points

Mar 4, 2008 5:38 PM in response to Alley_Cat

Thanks for the advice, Alley_Cat. Appreciate your pointers.

As I posted on another thread, renaming it to .m4v helped play in QT with good video, but broken audio. So, I gave the .ts file to my colleague and he just now reported that VisualHub doesn't handle .ts files. He has ordered the new EyeTV (v3) to see how that one deals with the recording and compatibility with ATV. Both of us went to the local Apple store, but they don't have the new version in the retail stores as yet.

However, I am wondering why HB doesn't transcode it to correct audio format. I guess I should ask this question in the HB forum.

Is your academic interest tickled enough to experiment with this .ts file? It is about 40MB size. But, I don't know how to send it to you because it is a large file. I could reduce the length further to bring it under 10MB in which case my Yahoo mail can handle it.

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Answer 11

Mar 4, 2008 6:06 PM in response to new2appletv

Did you try mpegstreamclip as AC suggested, if so and you had no joy give VLC a whirl.

eyetv does a wonderful job of recording tv for the tv but I doubt it will be much help with the files you have already.

If all else fails you could try HDTVtoMPEG2, but it's a bit more complicated to use.

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Answer 12

Mar 5, 2008 2:11 PM in response to Winston Churchill

MPEG Streamclip for mac definitely can work with .ts files, I do it all the time. I would assume the PC version could as well. The only gottcha is that the Mac version needs to have the QT MPEG-2 codec installed (buy from Apple, $20), don't know about the PC.

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Answer 13

new2appletv Author

Level 1

40 points

Mar 5, 2008 5:59 PM in response to Matt Larson2

I love this mpegstreamclip tool for Windows. Thanks Alley_Cat.

It installed an alternate QT player with the MPEG-2 plugin and then it was able to convert the .ts file to Apple TV 720p HD preset (5mbps bit rate unlike the 2.5mbps preset in HB) and I was able to add this file to iTunes and play it there. I am going to try this file on Apple TV tonight.

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Answer 14

new2appletv Author

Level 1

40 points

Mar 6, 2008 7:28 AM in response to new2appletv

All the files I created so far using mpegstreamclip or VLC play in iTunes, but Apple TV doesn't recognize it. The preset for ATV in mpegstreamclip puts the bit rate at 5mbps, which should work. I tried it at 2.5, but that didn't work either. I used VLC (a tool that I generally use to playback a ts) to convert to H.264, but again iTunes plays it, ATV doesn't recognize it.

I have used HDTVtoMPEG2 tool many times, but I used to use it primarily to strip out a single service from the muxed stream to reduce the file size when we want to test a specific issue with a stream. The version that I have 1.11.89 can only create ts and mpeg2 files. I used it in my first step to cut the 4hr Super Bowl recording to the 30sec file that I am experimenting with. I had saved it as ts and mpeg2 and then tried HB on both of these outputs. HB outputs also don't get recognized by ATV. Is there a newer version of HFTVtoMPEG2 that generates H.264 output?

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Answer 15

Jun 1, 2008 1:33 PM in response to new2appletv

Note: The just released Hauppauge HD-PVR creates .ts in H.264 in realtime when connected to the component video output of most any device, and future software releases will pass-thru AC3 audio. I am anxious to see if its 720p output will be playable without transcoding on the AppleTV that I have upgraded with Perian v1.1 and ATVFiles.

v1.3 of the software that ElGato provides with its hardware Turbo.264 does now successfully transcode 1080i H.264 sample output files into 960x540 files playable on a stock ATV. This new version also supports AC3 passthru.

In that regard, I have experimented and posted my finding in the VisualHub forum on transcoding files at 720p 30 fps at bitrates beyond those limitations specified by Apple. I have successfully played these files on my ATV upgraded as noted, since iTunes will not sync a file beyond the ATV specs.

You can download some of these samples from my iDisk Public Folder: MichaelLAX.

HB will only work currently with .ts files that are encoded in MPEG-2.

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