2013-05-07, 04:11
I found something that I believe is a bug, but before I file a formal report in the tracker I thought that I ought to ask here first if I am the only one seeing this. (I did make some effort to see if this might be a duplicate of an existing bug report, but searching either the forums or the bug tracker data base for "thumbnail" turns up about a million or so matching hits in each case, and thus it is not practical for me to try to exhaustively go through all of those looking for reports of the bug I think I have seen.)
The bug appears to me to be non-platform specific, which is why I am posting about it here. I have verified that the same problem exists on (1) Windows 7 and (2) OpenELEC (Linux) and also (3) FreeBSD.
In a nutshell, I have amassed a large number of video files from a variety of sources. These run the gamut, and are composed of video streams encoded using various different video codecs (and various different levels thereof), various different audio codecs, and various different container types. In most instances, a thumbnail of one frame of each video is displayed, as it should be, when I hover over the name of the corresponding file in the Confluence video files browser. However in some rare cases, even though the video file in question can be played just fine with XBMC, no thumbnail is ever generated for that particular video file. This is not just a matter of some lag. It doesn't matter how long I wait. For these few specific files, XBMC/Confluence never generates a thumbnail.
The thumbnail generation fails consistently for certain specific video files from my collection, regardless of whether I am using XBMC on Windows, on Linux, or on FreeBSD to browse the files in question. (Interestingly, the set of video files for which the thumbnail generation fails on Windows and FreeBSD appears to be a proper subset of those for which it fails when using the latest OpenELEC 3.0.2, so there may even be an additional and separate thembnail problem relating only to that.)
I've tried to see if there is any pattern to the failures, but I've only been marginally successful at this. Almost always, the failures occur only for .WMV files, however I did see one lone instance for which there was a failure also for one specific .MP4 file. .AVI files and .MPG (MPEG2) files never seem to exhibit the problem.
Among the failures for .WMV files, it does seem that perhaps files that are identified as follows, by the mediainfo tool, are ones for which the failure SEEMS to always occur:
... VC-1 (WMV3)(Main)
Other failures also occurred for files identified by mediainfo as follows:
... VC-1 (Microsoft)(Advanced@L1)
... VC-1 (Microsoft)(Advanced@L3)
however I have some other .WMV files that mediainfo says exactly the same thing about, and for those, XBMC has no trouble at all generating the thumbnails. I saw zero failures in the case of various files that mediainfo identified as follows:
... VC-1 (WMV3)(MP@ML)
... VC-1 (WMV3)(MP@HL)
Please be aware that I am just looking for patterns and that in fact I have virtually no understanding of the various video codec descriptions written above.
I also saw one failure to generate a thumbnail on a single .MP4 file that mediainfo described as follows:
... AVC ([email protected])(CABAC/5 RefFrames)
Has anyone else seen the kinds of failures (to generate video thumbnails) that I have described?
I almost forgot to mention this. On Windows I am using XBMC 12.1 official release. On FreeBSD I am using 12.0 release. Embedded within the OpenELEC 3.0.2 release seems to be some pre-release version of XBMC 12.2. In all cases I am using the stock Confluence skin.
The bug appears to me to be non-platform specific, which is why I am posting about it here. I have verified that the same problem exists on (1) Windows 7 and (2) OpenELEC (Linux) and also (3) FreeBSD.
In a nutshell, I have amassed a large number of video files from a variety of sources. These run the gamut, and are composed of video streams encoded using various different video codecs (and various different levels thereof), various different audio codecs, and various different container types. In most instances, a thumbnail of one frame of each video is displayed, as it should be, when I hover over the name of the corresponding file in the Confluence video files browser. However in some rare cases, even though the video file in question can be played just fine with XBMC, no thumbnail is ever generated for that particular video file. This is not just a matter of some lag. It doesn't matter how long I wait. For these few specific files, XBMC/Confluence never generates a thumbnail.
The thumbnail generation fails consistently for certain specific video files from my collection, regardless of whether I am using XBMC on Windows, on Linux, or on FreeBSD to browse the files in question. (Interestingly, the set of video files for which the thumbnail generation fails on Windows and FreeBSD appears to be a proper subset of those for which it fails when using the latest OpenELEC 3.0.2, so there may even be an additional and separate thembnail problem relating only to that.)
I've tried to see if there is any pattern to the failures, but I've only been marginally successful at this. Almost always, the failures occur only for .WMV files, however I did see one lone instance for which there was a failure also for one specific .MP4 file. .AVI files and .MPG (MPEG2) files never seem to exhibit the problem.
Among the failures for .WMV files, it does seem that perhaps files that are identified as follows, by the mediainfo tool, are ones for which the failure SEEMS to always occur:
... VC-1 (WMV3)(Main)
Other failures also occurred for files identified by mediainfo as follows:
... VC-1 (Microsoft)(Advanced@L1)
... VC-1 (Microsoft)(Advanced@L3)
however I have some other .WMV files that mediainfo says exactly the same thing about, and for those, XBMC has no trouble at all generating the thumbnails. I saw zero failures in the case of various files that mediainfo identified as follows:
... VC-1 (WMV3)(MP@ML)
... VC-1 (WMV3)(MP@HL)
Please be aware that I am just looking for patterns and that in fact I have virtually no understanding of the various video codec descriptions written above.
I also saw one failure to generate a thumbnail on a single .MP4 file that mediainfo described as follows:
... AVC ([email protected])(CABAC/5 RefFrames)
Has anyone else seen the kinds of failures (to generate video thumbnails) that I have described?
I almost forgot to mention this. On Windows I am using XBMC 12.1 official release. On FreeBSD I am using 12.0 release. Embedded within the OpenELEC 3.0.2 release seems to be some pre-release version of XBMC 12.2. In all cases I am using the stock Confluence skin.
