[gstreamer-bugs] [Bug 577346] New: [xvimagesink] Playback failure with certain XVImage sizes

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | gst-plugins-base | Ver: 0.10.16
           Summary: [xvimagesink] Playback failure with certain XVImage
                    sizes
           Product: GStreamer
           Version: 0.10.16
          Platform: Other
        OS/Version: All
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: gst-plugins-base
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: steve.magoun at canonical.com
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: 2.21/2.22
   GNOME milestone: Unspecified


Please describe the problem:
For some content with dimensions that aren't a multiple of 2px/4px (e.g.
190x240), incorrect behavior in xvimagesink prevents the content from playing;
the user is presented with the error "Failed to create output buffer of X x Y".
The content plays properly if Xv output is disabled. It is not a hardware
limitation - the same content plays properly with Xv using other media players
like mplayer.

The problem seems to be that xvimagesink assumes that XvShmCreateImage will
return a surface with dimensions that have been silently adjusted by the video
driver. xvimagesink compares the size of the XvImage returned by
XvShmCreateImage with an expected size it computes, and throws the error if the
two size values differ.

This is an invalid assumption for drivers that don't adjust the size of the
surface (Intel's 'Poulsbo' driver - xf86-video-psb is one such example). The Xv
doc here http://www.x.org/docs/Xv/video says "[w]idth and height may be
enlarged in some YUV formats", but there's no indication that such enlargement
is a requirement.

Instead of assuming the video driver will adjust the image size, xvimagesink
should perform the adjustment itself.

Steps to reproduce:
1. Download + unzip sample_mpeg4.mp4 from http://support.apple.com/kb/HT1425
2. gst-launch-0.10 ! filesrc location=~/sample_mpeg4.mp4 ! decodebin !
ffmpegcolorspace ! xvimagesink


Actual results:
Error message: "Xserver allocated buffer size did not match input buffer";
content does not play

Expected results:
Content plays in a new window

Does this happen every time?
Yes

Other information:
Might be the underlying problem in bug 552796

My OS is Ubuntu 8.04.2


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