[Resolved] Losslessly convert downloaded vids and AAC files

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Ruby
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Re: Losslessly convert AAC to MP4

#16 Post by Ruby »

webfork wrote:
Ruby wrote:Add this to the 'Additional FFmpeg command-line parameters' field:

Code: Select all

-vn -acodec copy -f mp4
Thanks for the suggestion, but no luck with Pazera - could I perhaps be missing a codec? It seems to run but the file it generates can't be viewed by Foobar. (VLC can read it but VLC could view the original AAC file as well.)
Could this be related to line 4 of my previous post?

self-quote:
As an example (and much to my surprise) Foobar2000 will fail to open an AAC (MP4 encoded) file with a [.aac] file extension.
Rename/change the extension, e.g. [.aac > .mp4] and Foobar2000 will then work with it.
~Ruby

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Userfriendly
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Re: Losslessly convert AAC to MP4

#17 Post by Userfriendly »

Pazera with the "-vn -acodec copy -f mp4" command-line parameter produces an aac file that's actually an MP4. I assume you were trying to feed foobar the wrongly named audio file. You have to manually rename the .aac to .mp4/.m4a then foobar2000 can read it. That's the downside with the Pazera method, you have to manually rename the extension.

Why don't you try TAudioConverter again. It works just fine now. The last version you tried was bugged and it already has been updated several times. It's drag and drop and can automatically encode to whatever AAC extension you want (M4A, M4B, M4R, MP4, AAC).
http://sourceforge.net/projects/taudioconverter/files/
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Re: Losslessly convert AAC to MP4

#18 Post by webfork »

Ruby wrote:Could this be related to line 4 of my previous post?
Userfriendly wrote:You have to manually rename the .aac to .mp4/.m4a then foobar2000 can read it.
Yes, I did attempt a file rename.
Userfriendly wrote:Why don't you try TAudioConverter again. It works just fine now.
Sure, I'll give it another go.

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Re: Losslessly convert AAC to MP4

#19 Post by webfork »

Webfork wrote:
Userfriendly wrote:Why don't you try TAudioConverter again. It works just fine now.
Sure, I'll give it another go.
Some success: TAC (GPL v2) did the trick when pulling the data from the original video. Unfortunately, the program would not accept .AAC files so I couldn't convert stuff I already pushed from video into audio (this saved a lot of space). I'll probably try MP4Box for that.

Thanks Userfriendly for suggesting it again.

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Re: Losslessly convert AAC to MP4

#20 Post by webfork »

I got ambitious and tested out My MP4Box GUI - http://my-mp4box-gui.zymichost.com/download.html - req dotNET 3.5

Crashed when I dragged some AAC files into it. Might be a 64 bit issue rather than something with that program. No way of knowing if it was portable or not, but I couldn't 7-zip or UniExtract it.

Anyway, that was not a solution. The search continues.

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Re: Losslessly convert AAC to MP4

#21 Post by webfork »

Oddly someone over on youtube covered it while talking about audio+video container formats: https://www.youtube.com/watch?v=kx78xnYGdJQ

Need to run a few more tests before I say this issue is resolved, but XMedia Recode may be the way to go for no-reencode Youtube conversions.

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Re: Losslessly convert AAC to MP4 -- Resolved

#22 Post by webfork »

webfork wrote:Need to run a few more tests before I say this issue is resolved, but XMedia Recode may be the way to go for no-reencode Youtube conversions.
Finally solved this. XMedia Recode was the way to go.

Thanks everyone for your suggestions.

Steps:
  1. Add the AAC audio file
  2. On the Format tab, select "Custom" and choose Format: M4A
  3. In the Audio tab, select "Mode: Copy"
  4. Click "Add Job" (large green plus symbol)
  5. Click "Encode" (two icons to the right)
How do you know it wasn't reencoded?
Worked extremely fast, almost the level of a file copy. Any re-encoding usually takes about 5 minutes, this took about 30 seconds. Also, file size is roughly same.

Resolution Criteria
Files now run as desired in Foobar2000 with the ability to modify the progress bar (jump ahead or move back in the file). I haven't tested in my Rockbox-modified Sansa player yet, but I have little doubt that it will work fine. Big relief.

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Re: Losslessly convert AAC to MP4 -- Resolved

#23 Post by webfork »

I had a lot of files to convert over into a usable format and unfortunately I found that some files are working while others are not.

I found an AAC auto-convert utility inside streamWriter, but it appears to only work with incoming live streams rather than existing audio. Might make a request to their forums to see if that feature could be added. In the mean time, this topic is only resolved for some AAC-encoded files.

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Re: Losslessly convert AAC to MP4 -- Resolved

#24 Post by webfork »

So V2V's encoder added some interference to the output WAV files and after ongoing audio issues with XMedia, I'm going to try switching over to TAudioConverter again as UserFriendly suggested.

Still, I did find a cool trick with XMedia to do Volume Normalization and save to mono output:

1. Choose Settings: Format Tab:

Profile - Custom
Format - WAV
File Extension - wav

2. Audio Codec: PCM signed 16-bit Little Endian (default)

3. Audio Tab under "General"

Modus: Convert
Codec - PCM signed 16-bit Little Endian (default)
Sample rate 44100
Channels - Mono

4. Same tab under "Volume correction:" select Volume correction to Volume normalization (dB)

5. Click "analysis" and use the provided value

Caveats: Definitely check the results. Do not trust this program's output. Also, make sure you close the program ... although its a bit out of date, 3.1.1.0 kept taking up full processor usage even when I wasn't processing anything.
Last edited by webfork on Mon Dec 16, 2013 7:08 pm, edited 1 time in total.
Reason: (adding in a howto bit)

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Re: Losslessly convert AAC to MP4 -- Resolved

#25 Post by webfork »

webfork wrote:I'm going to try switching over to TAudioConverter again as UserFriendly suggested.
Testing so far on this has been very positive. TAC http://www.portablefreeware.com/?id=2556 is obviously the way to go for lossless conversions.

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Re: [Resolved] Losslessly convert AAC to MP4

#26 Post by webfork »

Alternate solution: several portable, music-only downloaders have appeared since I posted about this including TEncoder and 3D Youtube Downloader. As these tools are not 100% reliable, this guide may still be useful.

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Re: [Resolved] Losslessly convert downloaded vids and AAC fi

#27 Post by Midas »

Don't know if it's still needed or even if it fits the bill (I haven't tested it!), but I felt like mentioning free M4A to MP3 here...
http://www.m4atomp3.com/ wrote:M4A to MP3 is a free audio converting software to convert M4A/AAC audio (*.m4a;*.aac;*.m4r;*.m4b;*.mp4;*.3gp) to normal MP3 audio files (*.mp3). It supports batch conversion and drag-drop feature, you can easily convert a lot of audio files in one time. This software is freeware, lightweight and easy to use.
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Re: [Resolved] Losslessly convert downloaded vids and AAC fi

#28 Post by webfork »

Midas wrote:... even if it fits the bill (I haven't tested it!), but I felt like mentioning free M4A to MP3 here
This thread was more for lossless conversion tools, whereas MP3 to MP4 is going to be a lossy conversion. Unfortunately I did a bit of digging and couldn't find something specifically addressing MP4->MP3 conversion so I guess this thread is as good as any.

Anyway, the program looks good. Lots of options for your MP3s but defaults to 128. Good to have for people who don't have an Apple player (e.g. SanDisk devices).

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Re: [Resolved] Losslessly convert downloaded vids and AAC fi

#29 Post by Specular »

I use the MP4Box command line:

Code: Select all

mp4box -add input.aac output.m4a
Simple enough for me. Works better than ffmpeg's command I've found, which can sometimes come up with bitstream error messages.

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Re: [Resolved] Losslessly convert downloaded vids and AAC files

#30 Post by webfork »

Extract audio from downloaded videos via VLC

I found a number of HOWTOs that talked about this process, but all of them were focused on conversion rather than extraction. So I wrote my own.

So it's been a few years and I decided to revisit my process here. There are some ideas listed in thread that are still workable, but some are oudated. My current steps are a less intuitive process with VLC, but sometimes the best tool for the job is what's on hand. Free Audio Video Pack is more intuitive/straightforward but VLC is open, actively developed, cross-platform, and widely used. So it should be a safe option to come back to again and again.

Note that in this example I used an .MP4 file but the process should be something you should be able to follow with most common video formats. And yes it will work in batch to convert 10, 100, or 1,000 files at once.

Steps
  1. Open the file in VLC and check the format via Tools - Media Information
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  2. Click on the Codec tab and look for the info:
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  3. Now that you know the format, close the information window and, from the menu, select Media - Convert / Save
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  4. Click +Add and navigate to the file(s) you want to convert
  5. Select Convert from the Convert/Save drop down menu at the bottom
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  6. From this screen, modify the profile to list Audio - MP3 and then press the small wrench icon.
  7. From the Audio codec tab, check the box for Keep original audio track.
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  8. Here, you must tell the program what format this original audio track (from Step 3) is or it won't export correctly. Click back to the Encapsulation tab and select the format closest to yours. In this case, it's MP4/MOV.
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  9. Select a destination file and click Start. The conversion might start immediately or it might get queued up in the interface. You might have to click the triangle button in the lower left hand corner (Play) to get it to start the conversion.

Final notes - Timing: A 1 hour video should take less than a few seconds to process as it's just copying over the information -- nothing is being re-encoded. If it takes more than a minute, you may have a configuration problem where you're converting rather than extracting.

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