cx18: where do the transport stream PIDs come from?

cx18: where do the transport stream PIDs come from?

[Lars Hanisch]

Hi,

  while working on a small test app which repacks the ivtv-PS into a TS, I received a sample from a cx18-based card. The 
TS contains the video PID 301, audio PID 300 and PCR pid 101.

  Where do these PIDs come from, are they set by the driver or are they firmware given?
  Is it possible to change them?

Regards,
Lars.

Re: cx18: where do the transport stream PIDs come from?

[Andy Walls]

On Fri, 2010-02-26 at 17:23 +0100, Lars Hanisch wrote:
> Hi,
> 
>   while working on a small test app which repacks the ivtv-PS into a TS, I received a sample from a cx18-based card. The 
> TS contains the video PID 301, audio PID 300 and PCR pid 101.
> 
>   Where do these PIDs come from, are they set by the driver or are they firmware given?

For analog captures, for which the firmware creates the TS, the firmware
sets them.


>   Is it possible to change them?

It is not possible to tell the firmware to change them.  There are two
documented CX23418 API commands in cx23418.h:

CX18_CPU_SET_VIDEO_PID
CX18_CPU_SET_AUDIO_PID

Unfortunately, I know they do nothing and will always directly return
0x200800ff, which is a CX23418 API error code.

Regards,
Andy

> Regards,
> Lars.

Re: cx18: where do the transport stream PIDs come from?

[Lars Hanisch]

Am 28.02.2010 14:04, schrieb Andy Walls:
> On Fri, 2010-02-26 at 17:23 +0100, Lars Hanisch wrote:
>> Hi,
>>
>>    while working on a small test app which repacks the ivtv-PS into a TS, I received a sample from a cx18-based card. The
>> TS contains the video PID 301, audio PID 300 and PCR pid 101.
>>
>>    Where do these PIDs come from, are they set by the driver or are they firmware given?
>
> For analog captures, for which the firmware creates the TS, the firmware
> sets them.

  That's what I thought. So I will use the same IDs for my conversion of an ivtv-PS.

>
>
>>    Is it possible to change them?
>
> It is not possible to tell the firmware to change them.  There are two
> documented CX23418 API commands in cx23418.h:
>
> CX18_CPU_SET_VIDEO_PID
> CX18_CPU_SET_AUDIO_PID
>
> Unfortunately, I know they do nothing and will always directly return
> 0x200800ff, which is a CX23418 API error code.

  Good to know.

Thanks!
Lars.

>
> Regards,
> Andy
>
>> Regards,
>> Lars.
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>