Check AAC bitrate?

[CasanovaFly]

I'm looking for a way to check the bitrate of AAC files I've converted from DTS or AC3. Whenever I open them in MediaInfo, it just says "48kHz, 6 channels, AAC (Version 4) (LC)".

I ask because I tried Xvid4PSP, but whenever I encoded to AAC it spit them out ~150kbps lower than what I originally set them at.

Anybody able to shed some light on this?

[guns1inger]

I suspect you haven't spent much time with MediaInfo. Try switching views - Tree view will give you more information than will probably ever need. Text view is great if you want to paste that information in the forum.

[CasanovaFly]

I suspect you haven't spent much time with MediaInfo. Try switching views - Tree view will give you more information than will probably ever need. Text view is great if you want to paste that information in the forum.

Not located there. Can't find it no matter what view I try.

[poisondeathray]

you can calculate it

filesize = bitrate x running time

or put it into a container temporarily (e.g. yamb), then use mediainfo

[CasanovaFly]

you can calculate it

filesize = bitrate x running time

or put it into a container temporarily (e.g. yamb), then use mediainfo

It's in a container right now. I use MeGUI to convert it right "inside" the original MKV container (I just conver the audio, leave the original video). Still reads out nothing. However, when I extract the .aac file, it reads "Bit rate mode: Variable"; which doesn't make sense because I converted to CBR 640kbps.

As for getting the numbers through your calculations: the movie is 133 minutes long (7980 seconds), at 640kbps, so that should be about 5100000kb's. Which comes out to about 5000MB if I'm not mistaken. The file size for the extracted .aac file is about 614MB.

Unless there is some bits/bytes difference I'm missing out on, that is. Which is entirely possible.

[poisondeathray]

You can put it in an mp4 container temporarily, mediainfo will be more successful in reading the bitrate

or since you're using megui, you can use the bitrate calculator (just use it in reverse)

614MB audio works out to be about 640kbps

[CasanovaFly]

I'm not sure how I would use the bitrate calculator in reverse (I'm new to the program) and I have no idea how to easily put it into an MP4 container.

What was the math that you used for it to work out?

[poisondeathray]

640kbit/s is 0.64Mbit/s

0.64Mbit/s x 7980s = 5107.2Mbit

divide by 8 for bytes (8 bits in a byte)

5107.2Mbit / 8 = 638.4Mbytes

Or you can use the equation and work in reverse, given a file size. I hate doing math, so I just push the buttons in a bitrate calculator

[CasanovaFly]

The math will work just fine for me. It gives me the info that I need; or at least puts my mind at ease. I might peruse another outlet, just to see the numbers on the screen, but for now it'll work.

Thank you very much.

[thezanny]

Even I find it that mediainfo doesn't display the AAC bitrate in .mkv files

[CasanovaFly]

Even I find it that mediainfo doesn't display the AAC bitrate in .mkv files

Glad I'm not the only one. It's kinda silly, but oh well.

[DarrellS]

It's because of the container. As stated by poisondeathray, by sticking the files in an mp4 container, it does show the bitrate.

I would leave the audio as DTS or AC3 in an mkv container.

I don't know if Xvid4PSP has audio passthrough. I know that Handbrake does. I use Virtualdub with the external encoder to convert to h264 mkv and created an encoder set that does ac3 passthrough.

I just used Nero Wave Editor to convert a 6 channel AC3 file to AAC. Here is the MediaInfo text file...

Complete name : C:\Documents and Settings\Darrell\Desktop\Girls, Girls, Girls.aac
Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 18.8 MiB
Duration : 4mn 28s
Overall bit rate : 586 Kbps
Encoded date : UTC 2011-07-09 18:26:57
Tagged date : UTC 2011-07-09 18:27:43

Audio
ID : 1
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 4mn 28s
Bit rate mode : Variable
Bit rate : 576 Kbps
Maximum bit rate : 754 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 18.4 MiB (98%)
Writing library : Nero AAC codec Mar 12 2007
Language : English
Encoded date : UTC 2011-07-09 18:26:57
Tagged date : UTC 2011-07-09 18:27:43
Material_Duration : 273055
Material_Duration_LastFrame : -12
Material_StreamSize : 19594419

...and converted to mp4...

Complete name : C:\Documents and Settings\Darrell\Desktop\Mötley Crüe - Greatest Video Hits - Extras - 01 Girls, Girls, Girls (X-Rated Version)_Track2.h264-muxed.mp4
Format : MPEG-4
Format profile : Base Media
Codec ID : isom
File size : 108 MiB
Duration : 4mn 33s
Overall bit rate : 3 319 Kbps
Encoded date : UTC 2011-07-08 18:39:56
Tagged date : UTC 2011-07-08 18:39:56
Writing application : My MP4Box GUI 0.4.9.1 By Matt Bodin

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L3.0
Format settings, CABAC : Yes
Format settings, ReFrames : 4 frames
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 4mn 33s
Bit rate : 2 742 Kbps
Maximum bit rate : 5 298 Kbps
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 3:2
Frame rate mode : Constant
Frame rate : 29.970 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.265
Stream size : 89.5 MiB (83%)
Title : Imported with GPAC 0.4.6-DEV (build 1)
Writing library : x264 core 104 r1698 c41b8f0
Encoding settings : cabac=1 / ref=1 / deblock=1:-1:-1 / analyse=0x3:0x3 / me=dia / subme=1 / psy=1 / psy_rd=0.00:0.00 / mixed_ref=0 / me_range=16 / chroma_me=1 / trellis=0 / 8x8dct=1 / cqm=0 / deadzone=21,11 / fast_pskip=1 / chroma_qp_offset=0 / threads=6 / sliced_threads=0 / nr=0 / decimate=1 / interlaced=0 / constrained_intra=0 / bframes=3 / b_pyramid=2 / b_adapt=1 / b_bias=0 / direct=1 / weightb=1 / open_gop=0 / weightp=0 / keyint=250 / keyint_min=25 / scenecut=40 / intra_refresh=0 / rc=crf / mbtree=0 / crf=24.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:1.00
Encoded date : UTC 2011-07-08 18:39:56
Tagged date : UTC 2011-07-08 18:40:04

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 4mn 33s
Bit rate mode : Variable
Bit rate : 576 Kbps
Maximum bit rate : 745 Kbps
Channel(s) : 6 channels
Channel positions : Front: L C R, Side: L R, LFE
Sampling rate : 48.0 KHz
Compression mode : Lossy
Stream size : 18.7 MiB (17%)
Title : Imported with GPAC 0.4.6-DEV (build 1)
Encoded date : UTC 2011-07-08 18:40:02
Tagged date : UTC 2011-07-08 18:40:04

[CasanovaFly]

I don't want an MKV or MP4 container, though. I'm converting the AC3/DTS to AAC so I can then convert it easily to WMV for playback on my Xbox. I use Microsoft Expression Encoder and it's way too finicky with AC3 files (basically works one time out of 100) and it just hates DTS files.

[DarrellS]

Converting to aac makes even less since if you are converting to WMV.

You need to convert the 5.1 ac3/dts to 5.1 wave before trying to convert to wma. Use DGINDEX to demux MPEG video and 5.1 audio to 5.1 wave and then use Microsoft Expression Encoder to open AVS script and convert to WMV.

EDIT: I just opened a 5.1 ac3 mkv in MS Expression Encoder and had no problem converting to 5.1 wmv.

[CasanovaFly]

Converting to aac makes even less since if you are converting to WMV.

You need to convert the 5.1 ac3/dts to 5.1 wave before trying to convert to wma. Use DGINDEX to demux MPEG video and 5.1 audio to 5.1 wave and then use Microsoft Expression Encoder to open AVS script and convert to WMV.

EDIT: I just opened a 5.1 ac3 mkv in MS Expression Encoder and had no problem converting to 5.1 wmv.

What AC3 decoder did you use? Because I've been talking with MS staff about the issue and there are known incompatability issues with DirectShow-based AC3 decoders. I also got a couple passes through okay before everything went to hell, hence my reason of searching for either a new decoder and then abandoning that and looking to just use another form of audio.

[DarrellS]

AC3ACM and AC3filter.

Microsoft Expression encoder cannot handle DTS audio.

I have to give the same advice that everyone else always gives to the xbox users. Get a media player that was made to play all of your files instead of beating your heads against a wall trying to create something that will play on the xbox.

EDIT: It took me two days but I was finally able to take an mpeg with DTS audio (MediaInfo and other programs read it as 5.1 ac3 but none of my editors could handle the audio) and save the audio as 5.1 wav (maybe it was Nero Wave Editor). Created a mkv with video and no audio using external encoder in Virtualdub. Used Foobar to convert the 5.1 wav file to 5.1 ac3 (Microsoft Expression Encoder would not accept the audio from anything else, including the 5.1 wav). Used mkvmerge to mux the 5.1 ac3 with the mkv that I created with Virtualdub and then used Microsoft Expression Encoder to convert the mkv to 5.1, VC-1 WMV.

If I could use Windows Media command line encoders in Virtualdub then it would be a lot easier but since I will never use WMV for myself then I'm not too concerned about it.

I found a thread in a Microsoft Expression Encoder forum that stated with Windows 7 and some plugin that it has no problem with either AC3 or DTS (you have to go into preferences and turn off 3rd party ac3 decoders) but also stated that Silverlight does not support 5.1 audio so by default, it's set to downmix to stereo which is why you have to keep going in and changing the audio settings.

[CasanovaFly]

Well that's a lot to digest. My issues all occurred when using AC3Filter. It was confirmed by a MS rep to cause intermittent problems.

I use my Xbox to stream because when I decided to start streaming I had an Xbox. I'm finding it slightly ludicrous that so many problems have trouble converting or encoding anything to WMV, especially when they advertise themselves as the solution to all your encoding problems.

As for your steps, I have an easier way of converting DTS to AC3: Popcorn MKV AudioConverter. Been using that for years and it hasn't let me down. Used it with a different encoding program before I switched to Expression that wouldn't allow DTS, only AC3. That program messed with original frame rates, though, and led to stuttering, hence the switch.

If you could point me in the direction of that thread on the forum though I'd be very interested. From what I was told by the MS rep, DirectShow-based AC3 (and possibly DTS) decoders cause problems (I noticed it after a few initial successful runs) and the MS-based AC3 decoder in the Pro version was my only hope. But again, I'd be interested to read that forum post, if you still have it.

As of right now, it seems I've solved my problem in about as many steps as you. I convert to 5.1 AAC, however, using MeGUI. I prefer MeGUI and AAC to Popcorn and AC3, right now, because of the easy-to-use MeGUI UI and easy batch commands. I don't think getting AC3's working will really get my problem solved, but DTS will eliminate a big step. I usually deal primarily with DTS as the original audio file, so going straight from DTS would be best.

Thanks for all the help and research, though. You didn't have to do any of it, but it's appreciated.

[poisondeathray]

There are other alternatives to expression encoder - ones that work with DTS, and don't require so many steps, so you don't go through so many lossy stages (lose quality) or waste time

WMNicEnc - but requires simple 1 line avs script

I think Encode360, or EncodeHD and HDConvertToX (or autoMKV it was called in the past) can do it

[CasanovaFly]

I just checked out EncodeHD and it's not for me. I want a little bit more in terms of encoding options. Encode360 says it was discontinued in favour of EncodeHD, so I went HD first. It seems from the screens that 360 has a few more options, but I'm still looking for a slightly more advanced program. Looked at HDConverttoX as well and initially I'm just not digging the layout. I've gotten used to Expression right now, so I would like to stick with it if possible.

As for WMNicEnc, I don't know what an avs script is, nor how to create one.

[poisondeathray]

older versions of expression accepted .avs files , I am willing to be the latest one does too, so you could probably feed it an avisynth script (no large intermediate files, no extra processing steps or additional quality lost) . If you use ffms2, no need to install decoders, but you still need haali media splitter installed for mkv support

1) install avisynth

2) get ffmpegsource2 , unzip contents into avisynth/plugins folder, you need the .avsi and .dll specficially in the plugins folder to autoload
http://code.google.com/p/ffmpegsource/

3) open a file in notepad in the same directory as your mkv . Write the following, save it, change the extension from .txt to .avs. Make sure you have view extensions enabled in windows folder options. Change filename "video.mkv" to match whatever your video name is

FFMpegSource2("video.mkv", atrack=-1)

4) Open that .avs in expression or any other program like wmnicenc

[CasanovaFly]

Well, thanks for the heads up with avs scripts.

[DarrellS]

I couldn't get ffmpegsource2 to work and I couldn't get MS Expression Encoder to open AVS with AC3 or WAV audio. Kept getting Cannot find audio codec error.

I used DGindex to create the D2V file and used my AC3 file that I converted earlier since I could not get DGindex to demux a usable audio from my mpeg.

I used this command to work in WMnicEnc (I also have nicaudio plugin for Avisynth)...

LoadPlugin("C:\Unzipped\dgmpgdec157\DGDecode.dll")
a = MPEG2Source("E:\Music Videos\Uriah_Heep_Stealin.d2v")
b = NicAC3Source("E:\Music Videos\Uriah_Heep_Stealin.ac3")
AudioDub(a,b)

Converted audio to 5.1 wma using dBpoweramp and used this script...

LoadPlugin("C:\Unzipped\dgmpgdec157\DGDecode.dll")
a = MPEG2Source("E:\Music Videos\Uriah_Heep_Stealin.d2v")
b = DirectShowSource("E:\Music Videos\Uriah_Heep_Stealin.wma")
AudioDub(a,b)

...to open in MS Expression Encoder.

WMnicEnc with Nicaudio.dll is the best bet for 5.1 ac3 and DTS since you can use...

AC3: NicAC3Source
DTS: NicDTSSource
MPA: NicMPG123Source
LPCM: NicLPCMSource
RAW: RaWavSource


I have no problem opening an MKV with 5.1 ac3, 5.1 wav or DTS in MS Expression Encoder though so that is the easiest of all.

Here is the link for the error that you asked for...

http://social.expression.microsoft.com/Search/en-US/?query=Cannot%20find%20audio%20cod...+Encoder+Forum

...the third one I believe.

I tried playing my mpeg in windows media player as suggested in one of the threads and it would not play or download a codec but by putting the files in an mkv container, it allowed the file to play in both wmp and the expression encoder.

[Oly500]

AAC is still not compatible with some popular video players.
I got in the habit of re-encoding it before view on my smart tv.

And yes it seems MediaInfo still don't show the bitrate

Some sites don't allow AAC audio as well, I'm beginning to understand why...

[hello_hello]

AAC is still not compatible with some popular video players.
I got in the habit of re-encoding it before view on my smart tv.

And yes it seems MediaInfo still don't show the bitrate

Some sites don't allow AAC audio as well, I'm beginning to understand why...

Next to AC3, I'm fairly sure AAC would have the most player support. In fact I'm not sure when I last came across a device that didn't support it.

For MediaInfo to display the AAC bitrate, MKVs need to be muxed with MKVToolNix with it's track statistic tags option enabled (enabled by default these days). For MP4s, it should have no problem displaying the bitrate.