[mythtv-users] 16x9 stretch mode on ConvertX sourced streams

[Dave Pippenger]

After digging into the source it seems the change that made this impact is 
in libs/libmythtv/videooutbase.cpp.

A case statement was switched around a bit....

     // Override video's aspect if configured to do so
     switch (letterbox)
     {
         default:
         case kLetterbox_Off:
         case kLetterbox_Fill:
         case kLetterbox_16_9_Stretch:   XJ_aspect = videoAspect;
                                         break;

         case kLetterbox_4_3:
         case kLetterbox_4_3_Zoom:       XJ_aspect = (4.0 / 3);
                                         break;
         case kLetterbox_16_9:
         case kLetterbox_16_9_Zoom:      XJ_aspect = (16.0 / 9);
                                         break;
     }

kLetterbox_16_9_Stretch used to be grouped with the other 16:9 aspect 
ratio aspects and forced to a (16.0 / 9) aspect. Now it uses videoAspect 
which I had trouble tracking down where that comes from. I think it may be 
coming from some property of the video stream itself and is set at 4:3.

I don't think it's incorrect that if your choosing a 16:9 override that it 
should ignores everything uses 16:9. If there was a reason for the change 
or a better way to fix it let me know. Otherwise my patch is attached.

Dave Pippenger

On Thu, 16 Feb 2006, Dave Pippenger wrote:

>
>
> I enabled debugging on my frontend and as far as I can tell it's doing
> something when I change to 16:9 Stretch from 16:9, but it's just not doing
> the right thing...
>
> ==========================================================================
> These are the values from my plextor generated mpeg4 stream
>
> 16:9 Stretch...
>
> 2006-02-16 22:35:20.806 Image size. dispxoff 112, dispyoff: 0, dispwoff:
> 855, disphoff: 480
> 2006-02-16 22:35:20.806 Image size. imgx 0, imgy: 0, imgw: 720, imgh: 480
>
>
> 16:9...
>
> 2006-02-16 22:35:24.636 Image size. dispxoff 113, dispyoff: 0, dispwoff:
> 854, disphoff: 480
> 2006-02-16 22:35:24.636 Image size. imgx 0, imgy: 0, imgw: 720, imgh: 480
>
> ==========================================================================
>
> And these are the values from my pvr-250 mpeg2 stream
>
> 16:9 Stretch...
>
> 2006-02-16 22:41:06.352 Image size. dispxoff -30, dispyoff: 0, dispwoff:
> 1140, disphoff: 480
> 2006-02-16 22:41:06.352 Image size. imgx 0, imgy: 0, imgw: 720, imgh: 480
>
> 16:9...
>
> 2006-02-16 22:41:24.456 Image size. dispxoff 112, dispyoff: 0, dispwoff:
> 855, disphoff: 480
> 2006-02-16 22:41:24.456 Image size. imgx 0, imgy: 0, imgw: 720, imgh: 480
> =========================================================================
>
> So it seems it's not coming up with the right scaling of the image on an
> the mpeg4 stream for some reason. I'm going to try and dig into the source
> a bit and figure out what changed between 0.18 and 0.19 with the way it
> determines the output scale after applying aspect override.
>
>  Dave Pippenger
>
>
> On Wed, 15 Feb 2006, Dave Pippenger wrote:
>
>>
>> I have a dual tuner setup with a pvr-250 and a plextor ConvertX. I have been
>> using 16x9 stretch mode for some time but when I upgraded to 0.19 I found that
>> any streams coming from my Plextor no longer "stretch". The pvr-250 continues
>> to display I expect, but from what I can tell the plextor is showing 16x9
>> instead of 16x9 stretch. When I toggle the aspect ratio options I can see the
>> myth OSD change it's shape a bit, but the video remains exactly the same
>> between 16x9 and 16x9 stretch.
>>
>> If anyone has any ideas on how I can get my 0.18 16x9 stretch back I would
>> greatly appreciate it.
>>
>> Dave Pippenger
>>
>>
>> _______________________________________________
>> mythtv-users mailing list
>> mythtv-users at mythtv.org
>> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>>
>>
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>
>
-------------- next part --------------
diff -Naur old/mythtv-0.19/libs/libmythtv/videooutbase.cpp new/mythtv-0.19/libs/libmythtv/videooutbase.cpp
--- old/mythtv-0.19/libs/libmythtv/videooutbase.cpp	2006-02-07 13:56:06.000000000 -0800
+++ new/mythtv-0.19/libs/libmythtv/videooutbase.cpp	2006-02-17 01:00:03.000000000 -0800
@@ -385,15 +385,16 @@
     {
         default:
         case kLetterbox_Off:
-        case kLetterbox_Fill:
-        case kLetterbox_16_9_Stretch:   XJ_aspect = videoAspect;
+        case kLetterbox_Fill:           XJ_aspect = videoAspect;
                                         break;
 
         case kLetterbox_4_3:
         case kLetterbox_4_3_Zoom:       XJ_aspect = (4.0 / 3);
                                         break;
         case kLetterbox_16_9:
-        case kLetterbox_16_9_Zoom:      XJ_aspect = (16.0 / 9);
+	case kLetterbox_16_9_Zoom:
+	case kLetterbox_16_9_Stretch:   XJ_aspect = (16.0 / 9);
+
                                         break;
     }
 }