Re: Bug in PAT generator
"Johann Hanne" <[email protected]>
| Newsgroups | gmane.comp.video.videolan.libdvbpsi.devel |
|---|---|
| Message-ID | <[email protected]> |
You're right. I was mislead by the comment "header + CRC_32", actually it's "rest of header + CRC_32", and i was using the i_length field for copying the PSI section into a TS packet. Is there a better indicator for where the actual PSI data is (i'm using p_data), and how long it is (i'm now using i_length+3)? Furthermore my assumption that creating the PAT and copying it into a TS packet is all I have to do seems to be completely wrong, as VLC doesn't seem to like it. Also, the PAT-TS-packets coming from the satellites seem be somewhat different from what ISO/IEC 31818-1 says?? The section_syntax_indicator is set to 0, the reserved bits are set to 0 (the libdvbpsi PAT creator sets them to 1), the section_length field is always set to 0xb0 (176) and the section_number seems to be a per-transponder constant (I got 0xe9, 0xc7 and 0xc1)...?! Is there a extra spec for DVB PATs? Cheers, Johann > On Tue, Sep 23, 2003, Johann Hanne wrote: > > Hi all, > > > > PAT sections generated with dvbpsi_GenPATSections() have a wrong > i_length > > field. The reason for this are lines 426 and 448 in src/tables/pat.c: > > p_current->i_length = 9; /* header + CRC_32 */ > > "9" is wrong. It should be 12 (8 byte header + 4 byte CRC). Thus > replacing > > it with > > p_current->i_length = 12; /* header + CRC_32 */ > > fixes it. > > Well, I don't agree, since the spec says about the "section_length" > field : > > section_length - (..) It specifies the number of bytes of the section, > starting immediately following the section_length field, and including > CRC. Thus, we do not take into account the first 3 bytes. > > -- > Tristan > > > -- > This is the libdvbpsi-devel mailing-list, see > http://developers.videolan.org/ > To unsubscribe, please read http://developers.videolan.org/lists.html > If you are in trouble, please contact <[email protected]> > -- This is the libdvbpsi-devel mailing-list, see http://developers.videolan.org/ To unsubscribe, please read http://developers.videolan.org/lists.html If you are in trouble, please contact <[email protected]>