Revision as of 02:50, 3 November 2006

This is a feature request for a Filter Wizard for selecting and applying filters to recordings already recorded. This would allow the user to perform some basic video processing tasks in addition to transcoding.

Example: crop black bars from a TV show broadcast in letterbox.

Background

The functionality to apply filters to recordings already exists in the 'transcoders' profiles, but currently this method is not very user friendly (its just an argument string). There is some discussion on the developer mailing list of adding a gui for filters in the future, but nothing recent. Additionally, it is currently not possible to add new transcoder profiles, leaving only 4 possible combinations of compression and filtering.

The topic of allowing the user to add new recording profiles has been brought up on the developer mailing list. The position of the main developers seems to be "if you add a single new profile name, it would have to be added for each and every other profile group, etc, etc.. " and that this would be overly complex. It is assumed that the average user will not need more than 4 recording profiles. As far as I can tell the profiles in the 'transcoder' group would not have this issue. It is my understanding that 'transcoder' profiles are always used post recording and should then be hardware independent. Therefore a new profile in the 'transcoder' group would not need to be added to any of the other profile groups.

It is currently possible to add new transcoder profiles to the recordingprofiles table using a mysql query.

mysql> insert into recordingprofiles (name, videocodec, audiocodec, profilegroup) values("Letterbox","MPEG-4","MP3",6);

These profiles are then editable in the 'recording profiles' setup screen. They are also selectable from the 'post recording processing' options of the recording scheduler. However, these new profiles are not selectable from the osd menu of playing recordings. Currently the only selectable profiles from the osd are hard coded as "Default", "Autodetect", "High Quality", "Medium Quality" and "Low Quality".

Developer Threads

• PATCH transcoding profiles
• More recording profiles?
• More recording profiles? (revisited)
• [Preliminary patch[ Add profile groups
• How to edit the gui? (And some profile related stuff)

• Filter documentation?

Solutions

Suggested Solution

Fix transcoder profile setup to allow for adding new transcoders

• Add graphical interface for creating new transcoder profiles.
• Modify osd menu for playing recordings to show additional transcoder profiles.

Modify the transcoder profile wizard to make adding filter parameters easier

• Replace the 'custom filters' input box with 'Add filter'/'Remove filter'/'Modify Filter' buttons and a list of currently applied filters
• On 'Add filter' -> Provide a list of available filters
• On 'Select filter' -> Provide a wizard for each type of filter

Pros

• Should definatly work
• Fixes transcoder profile setup to allow for more profiles
• User only has to set parameters once and can use them on any video
• Filter parameters easily input
• Filters are more discoverable to user
• Seems to go along with the current architecture

Cons

• Possibly adds clutter to transcoder profile setup
• Will require some gui coding for wizards

Alternate Solution #1

Set the filters in the transcoder profile

Pros

• This should definitely work
• User only has to set parameters once and can use them on any video
• No new code

Cons

• Currently only 5 profiles and no option to add more.
• The current filter options are inconvenient to input from a remote.
• Filters aren't very discoverable.

Alternate Solution #2

Apply the filters in user jobs

Pros

• This should work
• No new code

Cons

• Not convenient to the user since they could not easily change filter parameters from a remote.
• Would require expertise.
• User would have to find a transcoder the would do the filtering. (maybe virtualDub or something)

Alternate Solution #3

Provide a filter menu for each recording

• Provide a menu item context menu of a recorded video (i.e. where 'edit' is). Allow the user to select filter parameters here and possibly preview.
  • Similare wizard to the first solution.
• Add videoFilter field to recorded table in database to store filter parameters for each recording
  • Perhaps other tables could be created, but this seems in line with how channel fitlers were implemented
• Modify transcoder to get filters from the recorded table, in (addition to / as apposed to) the recording profile.
  • What about conflicts

Pros

• Should work
• Allows user to choose custom filter parameters for each recording
• Should be easily discoverable for the user

Cons

• Probably would be redundant for user to select parameters for each recording if there are only several parameter sets the user uses for all their videos
• Possibly adds clutter to recorded video menu
• Requires change to MySQL schema
• Requires change to transcoder code
• Requires change to osd code?