[XviD-devel] About interlacing decoding & GMC issue

[CKHuang at via.com.tw]

Hi all,
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I downloaded the xvid source code & added Xv display support in the =
example code - xvid_decraw.c so that I could see the decoded video on =
screen.
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I got some cmp file (pure video bitstream which encoded by iso mpeg4 =
codec) to test. However, if the files have interlacing encoded or GMC =
encoded, warpping points =3D0, or 1, the video will decode error. If the =
warpping points =3D 2, or 3, the video decoded correctly through the Xv =
display.
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According to the iso/iec mpeg-4 specification, 7.7.2.1 Motion vector =
decoding in P- and S(GMC)-VOP:
there are 3 cases for the interlacing motion vector decoding.
However, I trace the interlacing part of the source code, it seems no =
related codes to implement this.
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Is it the reason that cause xvid decoded interlacing encoded file error =
?
So does the GMC encoded, warpping point =3D 0, or 1 file.
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Thanks for you guys' help,
Kevin Huang
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