IPod Video Conversion Guide

This page describes how to make your Video Files playable on an iPod.

Other "how to" pages

To play on this device, the file you copy to it needs to be of the correct format. This format is summarized below:

Video Codec	mp4v (MPEG4)
Audio Codec	mp4a (MP4 audio), aac (AAC)
Container	mp4 (MPEG4/MOV)
Size	320x240

iPod Video Conversion Guide for VLC 0.8.6a

Written by loqu (AKA Rob), http://www.kludgeroo.com/linked/videolan/vlc_ipod_converstion_8.6a.html

The following is a guide for converting (transcoding to file) any video that VLC Media Player (VLC) can play into a format that the Apple iPod can play. This should be "fool proof." This guide does not cover the process of putting those files onto an iPod. I've tested this guide on many containers, with and without subtitles. This is an evolving guide, so please refer to http://www.kludgeroo.com/linked/videolan/vlc_ipod_converstion_8.6a.html for the original.

Before I begin I'd like to thank the good people over at http://www.videolan.org for making a great multi-platform media program. I decided to make this guide, because I had to invest much of my time to get this to work. This is my way of giving back to the community.

Why Use VLC to Convert Video for the iPod?

If you're looking for the absolute highest quality in video conversion, then do NOT use VLC to convert Video for the iPod. There are many, probably too many, programs already available.

I prefer to use VLC to convert to iPod video, because I know that if VLC can play the file, then VLC can convert it for my iPod. I can also use VLC in a script, which means I can tie it into my intranet, run conversions automatically, and/or keep "profiles" (by using scripts) for each video format that I'd like to convert. In addition, converting to iPod video with VLC is very quick, because the encoder is only doing one pass. This means that VLC is not just good for converting to iPod video, but it is also good for converting to any type of video, where I need versatility and speed.

If considering the disk space on an iPod and the battery life, I think it is unnecessary to worry about file size/quality. Whereas a person can store their entire music library on an iPod, a person will not be able to store their entire video library on an iPod. At some point, that person will need to come home, dock the iPod, and transfer files. It is more likely that a movie, a music video, or at most a complete television series will be stored on the iPod.

Converting a Video with the Graphical User Interface

Open VLC. Please be sure you are using the default settings for VLC. Please be especially sure that you do not have "repeat" set, as you will infinitely overwrite your transcoded file.

Click "File" then "Open File", which will bring up the Open dialog.

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Be sure that you are on the File tab. Click Browse and select the file that you would like to convert. Now check the Stream/Save box and click the Settings ... button. This will open the Stream Output dialog. This is where the magic happens.

1. Notice that when you first open the dialog (if you haven't already tried to stream/save a file in this session) the Stream output MRL box at the top is empty. As you make your selections in the rest of this window, that box will fill up with your options in a form that the VLC executable understands.
2. First, check the File box, then click the Browse... button to the right. Now choose the name of the file that will be created during the conversion. Be sure to change the extension to "mp4".
3. Now choose the Encapsulation method. This is also known as the "container". Select MP4.
4. Go to Transcoding options next and check Video codec. Change the box to it's immediate right to h264. The next box to the right changes the bitrate of the video. I recommend 768 kb/s.
5. Still in the Transcoding options area, check the Audio codec box, and change the box to it's immediate right to mp4a. The next box to the right changes the audio bitrate. I recommend 64 kb/s or 96 kb/s.

So far, everything is fairly standard, but here comes the tricky part. Go back up to the "Stream output MRL Target:" box. Notice that the box is full of text. Look for the part that has #transcode{ }, and type width=320,canvas-height=240 somewhere inside the { }. Do not add extra spaces. This setting changes the width to 320 pixels and adds black bars above and below the movie, allowing all movies to maintain the appearance of their original aspect ratio. Be careful here. If you change any of the settings below this box, you will have to re-enter the width and height settings.

Click OK to close the Stream ouput dialog, then click OK to close the File open dialog. The movie should now start playing without showing the picture on the screen. When it is complete you should have an iPod compatible file.

Converting a Video through the Command-line

Conversion via the command-line is a little beyond the scope of this document, but using VLC in a script is my favorite way to convert videos. This generally allows me the leisure of dragging the file onto the script and magically getting my new iPod file in a certain directory.

Generally speaking, the format of the command can be:

vlc -vvv "my video.avi" :sout="#transcode{width=320,canvas-height=240,vcodec=mp4v, vb=768, acodec=mp4a, ab=96, channels=2}:std{access=file, mux=mp4, url=myvideo.mp4}" vlc:quit

On a Windows machine, I use the following batch script for drag and drop functionality. Once a file is dropped onto it, vlc converts the video to a folder that is set in the script.

  
  @REM Remove the quotes from %1 variable for vlc paramters
  @SET infile=%1
  @SET infile=%infile:"=%
  @REM Strip directory paths from %1 ...
  @FOR /F "delims=" %%i in ("%infile%") do SET filename=%%~ni
  @SET outdir=%userprofile%\My Documents\ipod video\
  @SET outfile=%outdir%%filename%.mp4
  @REM The following command should be on ONE line only.
  @REM Be sure to remove the carriage returns in your batch file.
  "C:\Program Files\VideoLAN\VLC\vlc.exe" -vvv "%infile%" :sout="#transcode{width=320, canvas-height=240, vcodec=mp4v, vb=768, acodec=mp4a, ab=96, channels=2}:standard{access=file,mux=mp4,url=%outfile%}" vlc:quit
  

Converting with Subtitles

The basic rule for subtitles is: if you can see them in VLC, then you can put them in your converted video; however, getting this to work can be tricky. Essentially, you use the soverlay option in the #transcode{...} section to tell VLC that it needs to combine the video and the subtitle streams into one video stream. Of course, that means nothing if you don't know how to get subtitles to display in the first place.

Subtitles for video can be stored in the orginal file as images or text. Subtitles can also come from a separate text file. It all depends on the original video file. Despite where the subtitles come from, you need to first get the subtitles to appear in VLC during normal playback.

If the subtitles are a part of the original file (as with DVD, SVCD, OGM, or MKV video), you will need to use the sub-track option to select the desired subtitle track. You will specify this option after the #transcode {...} section.

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To find the track numbers for the original file, play the file in VLC, click on the Video menu, and view the available tracks under Subtitles Track. The value that you will use for sub-track is the value in this list minus 1. From the picture above, you would specify sub-track=2 to get the second English track listed. (Use sub-track=5 for Deutsch.) To tie it all together, your #transcode{...} section would look like this:

  #transcode{...,soverlay}:stuff{...options...} :sub-track=2

Depending on the original file, you may also be able to get away with using the sub-language option instead of specifying the exact subtitle track. Note that this would play the first English track if we specified sub-language=English. Your #transcode{...} section would look like this:

  #transcode{...,soverlay}:stuff{...options...} :sub-language=English

Now that you have the video playing with subtitles, you can create a video with the subtitles overlayed on the video, using the same methods at the top of the document.

For best results, first transcode to file without setting a new width or height (the width=320,canvas-height=240 setting in the #transcode{...} section). After you have made the larger file with the subtitles overlayed, then convert to the smaller iPod width and height. This will make it so that your subtitles appear in the correct proportions on the smaller screen size.

Testing Your New File

Now as I stated earlier, I've run many tests on different input file formats and containers. Currently it is very rare for me to find a file that I cannot convert. As far as testing the file goes, I strongly recommend using Apple's Quicktime player. It is much faster than repeatedly transferring the video to your iPod, disconnecting the iPod, and playing the video. Unfortunately, Quicktime is only available on Mac and Windows.

Solving Problems with Your New File

Here are some of my most notable problems and their solutions.

VLC closes without outputting anything or the file is 0kb.

• Make sure you are only converting the movie, not a playlist.
• If you're using a script, make sure your script is correct. (I admit, the one I provided will probably have faults.)

My file is very small or only audio is recorded or only some of the video is present.

• More than likely, the input file is slightly corrupted in a spot or you are using the mp4v generic codec instead of the h264 codec. h264 really does work more consistently.
• Try adding fps=25,samplerate=44100 to the #transcode{...} section.
• Your CPU may be getting too hot. Seriously. This was happening to me on one of my machines, and when I tried it on another, conversion worked fine. Using a thermometer on the original CPU/heatsink, I discovered that the CPU jumped to 70 degrees during conversion! Solution: get another fan.

Notes

• The 5G and 5.5G of iPod video (with latest firmware) support video resolutions up to 640x480; however, the screen resolution is still 320x240. This may only be useful with subtitled videos, as it removes the second step of resizing the overlayed video.

Older version =

To make the video the correct size, you can edit the preferences, or run vlc from a command prompt.

vlc "input_filename" :sout="#transcode{vcodec=mp4v, vb=512, acodec=mp4a, ab=128, channels=2, audio-sync, width=320, height=240}:std{access=file, mux=mp4,url="output_filename"}" --aspect-ratio=width:height

This all goes on one line, and you'll need to fill in some of the values: the input and output filenames, plus the aspect ratio of the input file. By default vlc will stretch the video to the size specified by sout-transcode-height and width, but if you tell vlc the file's aspect ratio, it will scale and put a black border around it. The aspect ratio can be written as a ratio of width and height, with a colon between the two, or as a decimal.

Further I found that the iPod was particular about the parameter "channels" being set to 2. I found that without this parameter iTunes would import the file into the library but would not be able to upload the same to the iPod.

Further during my experiments I figured out that it was better to stick with MPEG4 encoding for the video stream. While H.264 codec is the latest video compression standard I found the resultant file size usually larger than when the MPEG4 compression mode was used, keeping all the other parameters like the resolution and the bitrate same. This definitely seems contradictory to what I would have expected but these were the findings of my experiments while using videoLan VLC media player.

(In fact, if the bit rates are chosen equally, the file sizes can be expected to be roughly the same. The advantage of h.264 over mpeg4 is its better video quality with the same bit rate or the allowance for lower bit rates and thus smaller files with comparable video quality.)

If you would like to try using H.264 set the parameter vcodec to h264 in the above command line as follows

vlc "input_filename" :sout="#transcode{vcodec=h264, vb=512, acodec=mp4a, ab=128, channels=2, audio-sync, width=320, height=240}:std{access=file, mux=mp4,url="output_filename"}"--aspect-ratio=width:height

A useful tip - If you intend to create a batch file that would transcode several titles in a DVD one after the other use the keyword vlc:quit as follows

vlc "input_filename" :sout="#transcode{vcodec=h264, vb=512, acodec=mp4a, ab=128, channels=2, audio-sync, width=320, height=240}:std{access=file, mux=mp4,url="output_filename"}" vlc:quit --aspect-ratio=width:height

Converting Oddly Sized Input Videos to View on the iPod Video

The command-line examples above did not work for me when converting video that did not already have a 4:3 aspect ratio. After converting the video, iTunes would not load the video into my library, and I would get "invalid data" errors when trying to view the file in the Quicktime Player. It seams as of at least version 8.6a (not tested on previous versions), vlc will use just the height value to determine the resultant width, while maintaining the original aspect ratio, not the specified ratio.

To remedy this, I used the sout-transcode-canvas-height option with the sout-transcode-width and removed the specific aspect ratio option and the specific height declaration. My example command-line is below:

vlc.exe -vvv "my video.avi" :sout="#transcode{vcodec=mp4v, vb=768, acodec=mp4a, ab=96, channels=2, samplerate=22050, width=320, canvas-height=240}:std{access=file, mux=mp4, url=myvideo.mp4}" vlc:quit

NOTE I've noticed that some files encoded with XVID come out without video. If this happens, try using vcodec=h264.

This command will start vlc, transcode the video to file, and quit when complete. The resultant video will be 320x240 with a black canvas filling in the height to the video borders. If the input is already has a 4:3 (320x240) aspect ratio, then no border will appear.

Here is an iPod format sample video converted with vlc.

Using Batch Files

Here is the info for a batch file to convert videos one after another, although you have to enter your input and output values yourself (use find and replace, or, if you are better than me, make an actual script/program). Make sure the output names are different or else it will get stuck and/or overwrite the old one

vlc "input_filename" :sout="#transcode{vcodec=mp4v, vb=512, acodec=mp4a, ab=128, channels=2, audio-sync, width=320, height=240}:std{access=file, mux=mp4,url="output_filename"}" vlc:quit --aspect-ratio=width:height

vlc "input_filename(1)" :sout="#transcode{vcodec=mp4v, vb=512, acodec=mp4a, ab=128, channels=2, audio-sync, width=320, height=240}:std{access=file, mux=mp4,url="output_filename(1)"}" vlc:quit --aspect-ratio=width:height

......etc for each video to convert (useful for converting short .flv or .gvi, or pretty much any file) I relise this is inefficient,

but hopefully someone will make a script (vlc seems best for making ipod videos from any source). NOTE2: I find that if i have spaces in the output it doesn't work, but this seems to be a problem with the .bat file. just don't use spaces and use an autorenamer to rename ([1]) NOTE: If you can somehow to get 264 to work (megui makes it work...) just change vcodec=mp4v to vcodec=h264.

The script to drag and drop files (for Windows) is as follows:

C:\PROGRA~1\VIDEOLAN\VLC\VLC -vvv %1 :sout=#transcode{vcodec=mp4v,vb=512,acodec=mp4a,ab=128,channels=2,width=320,height=240}:duplicate{dst=std{access=file,mux=mp4,dst=%1.m4p}} pause There is no problem with spaces in filenames.

This is also described (with snapshots) on http://tom.zickel.org/vlcmp4/

This has also been discussed in the forum

I followed these steps and was able to watch and listen on the ipod. The recorded audio level was pretty low, is there a way to make the audio louder in output_filename ?