[linux-dvb] dvbstream fails to tune QAM-256
lionteeth at cogweb.net
Mon Nov 22 02:59:00 CET 2010
On 11/19/2010 11:51 PM, David Liontooth wrote:
> I'm using Debian's dvbstream 0.6+cvs20090621-1 to capture video and
> closed captioning to file.
> If I tune with azap, dvbstream works fine, but I can't get it to tune
> on its own.
> In the Debian source code, I activated DVB_ATSC by adding -DDVB_ATSC
> to CFLAGS in the Makefile.
> dvbstream -f 645000000 -qam 256 -v 49 a 52 -o > test.ts
> gives me the error "Unknown FE type".
> Suggestions? Is this a problem with an API that has changed since
> dvbstream's last release?
If I change tune.h to allow DVB API >=3 major instead of just ==3, I get
this (this is a very lightly patched version to allow 8 cards):
# dvbstream -f 621000 -qam 256 -v 8192 -a 8192 -s 6875 -n 10 -o:test.ts
dvbstream v0.7.01 - (C) Dave Chapman 2001-2004
Released under the GPL.
Latest version available from http://dvbtools.sourceforge.net
Open file test.ts
Tuning to 621000 MHz
Using DVB card "Samsung S5H1411 QAM/8VSB Frontend", freq=621000
tuning ATSC to 621000000, modulation=5
Getting frontend status
Event: Frequency: 621000000
Bit error rate: 0
Signal strength: 0
FE_STATUS: FE_HAS_SIGNAL FE_HAS_LOCK FE_HAS_CARRIER FE_HAS_VITERBI
MAP 0, file test.ts: From -1 secs, To -1 secs, 0 PIDs -
dvbstream will stop after 10 seconds (0 minutes)
Streaming 1 stream
Caught signal 1 - closing cleanly.
So it tries to tune, and succeeds in a manner of speaking -- if I try to
tune to an unavailable frequency, it will fail; here we can see it
locks. However, the Signal strength is zero and the file is empty.
What happened with the ATSC QAM-256 tuning in between DVB API 3.1 and
now? I'm running 126.96.36.199, with DVB API 5.1.
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