caught exception: 
Postcondition violation!
error in png_read_row(): Read Error
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/png.cxx:381)

convert-im6.q16: unable to open image `/tmp/frame-050-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-050.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-050-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-051-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-051.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-051-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-052-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-052.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-052-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-053-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-053.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-053-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-054-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-054.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-054-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-055-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-055.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-055-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-056-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-056.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-056-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-057-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-057.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-057-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-058-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-058.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-058-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-059-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-059.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-059-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-060-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-060.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-060-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-061-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-061.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-061-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-062-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-062.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-062-0000.tif': No such file or directory
caught exception: 
Precondition violation!
did not find a matching file type.
(/build/libvigraimpex-EwHRK6/libvigraimpex-1.10.0+git20160211.167be93+dfsg/src/impex/codecmanager.cxx:234)

convert-im6.q16: unable to open image `/tmp/frame-063-0000.tif': No such file or directory @ error/blob.c/OpenBlob/2701.
convert-im6.q16: no images defined `frame-063.png' @ error/convert.c/ConvertImageCommand/3258.
rm: cannot remove '/tmp/frame-063-0000.tif': No such file or directory