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<blockquote data-quote="tourettes" data-source="post: 521248" data-attributes="member: 10858">Berns I have to say that you are a little bit off on your comments. CRC checksums are sent with the stream and their sole purpose is to allow application to verify the received data (it works such way even in other than DVB context). There is no other way to detect &quot;the one bit that is wrong in the stream&quot;. Just think how you would be able to detect the &quot;00000001&quot; from &quot;00000011&quot;. Both are valid, but it might have invalid data for the context, like telling that some descripor (EPG or any else) lenght is wrong. In that example we could run into memcpy that accesses the memory outside the boundaries it is allowed to access, causing a crash.Such small change can cause a crash and it wont be visible in any signal level or quality measurements (especially when BDA drivers are known to report false information pretty often, depending on the HW manufacturer).</blockquote>

[QUOTE="tourettes, post: 521248, member: 10858"] Berns I have to say that you are a little bit off on your comments. CRC checksums are sent with the stream and their sole purpose is to allow application to verify the received data (it works such way even in other than DVB context). There is no other way to detect "the one bit that is wrong in the stream". Just think how you would be able to detect the "00000001" from "00000011". Both are valid, but it might have invalid data for the context, like telling that some descripor (EPG or any else) lenght is wrong. In that example we could run into memcpy that accesses the memory outside the boundaries it is allowed to access, causing a crash. Such small change can cause a crash and it wont be visible in any signal level or quality measurements (especially when BDA drivers are known to report false information pretty often, depending on the HW manufacturer). [/QUOTE]

Verification