Video Conversion with DownloadHelper

What is it about

DownloadHelper's primary job is to retrieve to your disk the videos that are playing in Web pages, in their original format.

Unfortunately, the native format (generally FLV) is often not very convenient when it comes to playing back the videos, on either your home computer or a hand held device, burning them to a DVD or reworking the movie.

With the new DownloadHelper's Video Conversion feature, you can very easily select one or more videos that lie on your disk and choose a pre-defined output format. The program will process the movies in background.

Even better: you can setup the extension to automatically convert the videos as soon as they are saved by DownloadHelper. You can even specify conversion rules (which site, which original media format) to be processed with a given set of parameters.

Video conversion is available on DownloadHelper 3.1 or later.

Easy or powerful ?

Both :)

While you can select an output format by choosing it from a drop-down list, you can also fine tune the program to deal with dozens of parameters, like the size of the video, the bitrates to be generated, the number of frames per seconds, the audio and video codecs to be used and many more, including multi-pass conversions for an optimal result.

How does it work ?

DownloadHelper doesn't do the conversion by itself: this type of job is not really suitable for a Mozilla extension. Instead, it relies on the well-known FFmpeg program to do the conversion task, and provides the necessary glue to make it simple and convenient for DownloadHelper users.

FFmpeg is the most powerful video conversion utility. In fact, this is the back-end program used by most video converters on the market.

On Linux and Mac, DownloadHelper accesses directly the FFmpeg version you installed on your system. On Windows, this is simpler as you install directly an application, ConvertHelper, to make easier the DownloadHelper/FFmpeg relationship.

Installing the feature

Installing on Windows

Using video conversion with DownloadHelper requires that you turn on the feature from the extension's preferences dialog.

The simplest way to open the preferences is to right click on the DownloadHelper icon and select the first entry 'Preferences'. If the icon is not installed in the toolbar, the preferences can also be opened from the Tools / DownloadHelper / Preferences menu, or Tools / Add-ons menu, DownloadHelper selection, Preferences button. From the preferences window, the tab Conversion must be selected.

The Conversion enabled input must be checked.

The message in red indicates that ConvertHelper, the external program in charge of the conversion job, has not been found on the system. Clicking on the Install/Update converter button takes the user to a page where a ConvertHelper installation program can be downloaded from.

Installing ConvertHelper is an easy job:

Once ConvertHelper is installed, click on the Re-check Converter button or reopen the preferences.

Video conversion is ready to be used.

Installing on Linux and Mac

For Linux and Mac, we do not have a specific FFMPEG distribution to connect to DownloadHelper. Instead, the conversion relies on the distribution that has been installed separately on the computer. Of course, this can lead to conversion failures as the version of FFMPEG may not have been compiled with the features required by the chosen conversion parameters. This might be the case, for instance, when converting to MP3 format, as the native FFMPEG may not have this feature for legal reasons.

On Linux Ubuntu, you may install FFMPEG with:

sudo apt-get install ffmpeg

Or better, recompile FFMPEG with more features.

You can specify the exact location of the FFMPEG executable in the preferences.

Note that you can also use Mencoder as an alternative to FFMPEG. However, all the defined conversion parameters will simply be ignored.

Using the feature

Converting manually

Manual conversion allows the user to choose a set of video files from the standard File open dialog, and to indicate what output format is desired. The program takes care of doing the conversion job.

Right-click on the DownloadHelper icon and choose Convert videos. A file chooser dialog opens.

Several files can be selected by holding the CTRL or SHIFT key while clicking on the file name.

You can also request a video conversion at the same time you request the download of the video. For doing this, hold the SHIFT key while clicking on the entry in the download menu.

Then, the user is prompted for the desired output format.

In the basic usage of the conversion feature, the user chooses a pre-defined format in the drop-down list and click OK. Conversion will start immediately.

For advanced users, it is possible to tune many parameters of the conversion. Clicking Details opens a new dialog.

The most common conversion parameters are displayed. To be used, the corresponding checkbox must be checked, otherwise, the default applies.

Conversion parameters are dispatched within 2 tabs. The Advanced tab holds a special Extra parameters input to be used as FFMPEG arguments when the corresponding parameter is not listed in the user interface.

If the 2 Passes checkbox is active, the user can specify independantly the parameters for each pass. By default, the second pass uses the same parameters as the first one. When using 2 passes conversion, the input file is first processed to gather statistics on the audio and video streams, then the file is converted in the second pass with optimal tuning, leading to a better quality and/or a reduced size. This is of course at the price of a longer execution.

Converting automatically

It is possible to specify that conversion should occur automatically. By default, when the conversion feature is enabled, the downloaded FLV files are automatically converted to AVI. This is done using the default conversion rule. This rule can be edited to indicate a different format or parameters. Selecting the rule from the preferences dialog / conversion tab, and clicking button Edit rule opens the rule editor.

If the user needs to convert differently depending on the site he/she is accessing to, or the format of the original media files, it is possible to create several rules, that will be checked in order.

Button Revert to default removes all defined rules and re-create the default one.


Registration benefits

We detected that you are not running Windows as your operating system.

Registration is useless for you as the video conversion is already unrestricted on your operating system.

Registration of the video converter is useful if you are running Windows. It gives the following benefits:

  • Converted videos do not longer have the ConvertHelper logo at the top left corner
  • You can convert a video to a MP3 file in case you are only interested in the audio
  • You have access to our support service

Logo on converted video

The logo appears at the top left corner of the converted videos when you use the conversion on Windows with an unregistered converter version.

This logo has a fixed size. This means that if you convert a regular-sized web video (e.g 320x240), it will occupy a small portion of the video. If you use the converter on a small size video (e.g 160x120), it displays on a substantial part of the image.

You can get rid of the logo by registering your converter version.

Converting to MP3

On Windows, converting downloaded videos to MP3 format is only available on registered versions.

On other systems, Linux or MacOSX, converting to MP3 relies on the capabilities of the ffmpeg version that is installed on your system. You may need to recompile ffmpeg in order to get access to MP3 codec. Sorry, we don't provide support on this.

How to register

You can register your converter version from our registration page. As soon as the operation is complete you receive by mail your personal registration code. Copy this code to the input field of the dialog that opens when you select Register conversion in the DownloadHelper menus (note this menu option only appears if you are running DownloadHelper on Windows with an unregistered version of the converter and you have enabled conversion in the preferences).

When you reinstall your computer, your Firefox version or create a new user profile, your registration code will be checked automatically (or you may need to re-enter the code manually) for validity from our servers. After a number of reinstallations, the registration code will be blocked and you will automatically receive a mail to your original address. This mail contains a link that you need to visit in order to unblock your license.

Other stuff

Monitoring conversions

Conversions are performed on a one by one basis in order to avoid too much processing on the computer. Conversion jobs are queued in a list. It is possible to see the state of the queue by right-clicking on the DownloadHelper icon and selecting Converter queue.

Known issues

  • On Windows, the background converter opens a console. This happens on Firefox 2 and has been solved in the official release of Firefox 3. See the related bug for details.
  • On Firefox 3, prior to Firefox 3.0rc2, the browser freezes during the time of the conversion. Please, do not use an Firefox 3.0 beta version. For details, see Firefox bug #433005.
  • Firefox crashes when converting videos while the Converter Queue dialog is open. [Fixed in 3.1.1]This issue has been reported a couple of times on both Windows and Linux. It might be a side effect of the fix of Firefox bug #433055. We are investigating on this. For now, you might want to avoid opening the Converter Queue dialog while conversions are in progress.

Solving problems

If you play with conversion parameters, chances are that at some point we will have an issue: either no converted file will be generated, or the generated file won't play on your computer.

For the second case, there 99% chances your system is lacking a non-standard audio or video codec. You may want to install additional codecs, for instance the K-Lite Codec Pack.

If no converted file is being generated, it can be:

  • a conflict between FFMPEG parameters. There are many cases where 2 parameters just cannot be used together.
  • your version of FFMPEG does not support one or more parameters. This can happen particularly on Linux and Mac systems, as the conversion feature relies on the user-installed FFMPEG distribution.

On Windows only, it is possible to see the conversion log that will certainly give good indications about the issue.

Open the conversion tab of the preferences dialog and check Log conversions.

Perform a conversion, then come back and click Show log

Import/Export conversion formats

As fine-tuning conversion might be a tricky job, you may find convenient to be able to save and retrieve conversion configuration data. For doing so, right click on the Video Output Format window (not on a widget but on the window background). This opens a context menu with the option Copy video format. If you choose this option, the current configuration data are stored as a text string into the clipboard. You can paste it to a text file for later retrieval.

Similarly, if the clipboard contains a text string that can be understood by DownloadHelper, you will see a second menu entry, Paste video format, that will update the current format from the clipboard data.

Prevent conversion

  • If you don't want to use conversion at all, the best way is to disable the feature from the extension preferences.
  • If you want to convert only on demand without automatic conversion, you should enable the conversion from the extension preferences but remove any conversion rule. You will still be able to use manual conversion from Convert videos menu or SHIFT-click on the download menu entries.
  • If you want automatic conversion in general but not for a particular video, SHIFT-click on the entry in the download menu, then choose Cancel in the Output format dialog. You will then download the file in its original format.

Source code

You can download ConvertHelper source code from this link.

To be compliant with FFmpeg rules, we also provide the sources we used to build the converter package. However, if you plan to recompile FFmpeg you should better download the latest code by following the procedure described there.