X-Git-Url: http://pere.pagekite.me/gitweb/homepage.git/blobdiff_plain/76754b531a4a41ef2c1dba2677a68f342419a72f..50bdd9b4980ce7c170ea96130baf667c5affe05f:/blog/index.rss?ds=inline diff --git a/blog/index.rss b/blog/index.rss index 1fb55cc348..085c7f3828 100644 --- a/blog/index.rss +++ b/blog/index.rss @@ -6,6 +6,39 @@ http://people.skolelinux.org/pere/blog/ + + CasparCG Server for TV broadcast playout in Debian + http://people.skolelinux.org/pere/blog/CasparCG_Server_for_TV_broadcast_playout_in_Debian.html + http://people.skolelinux.org/pere/blog/CasparCG_Server_for_TV_broadcast_playout_in_Debian.html + Tue, 15 Jan 2019 00:10:00 +0100 + <p>The layered video playout server created by Sveriges Television, +<a href="https://casparcg.com/">CasparCG Server</a>, entered Debian +today. This completes many months of work to get the source ready to +go into Debian. The first upload to the Debian NEW queue happened a +month ago, but the work upstream to prepare it for Debian started more +than two and a half month ago. So far +<a href="https://tracker.debian.org/pkg/casparcg-server">the +casparcg-server package</a> is only available for amd64, but I hope +this can be improved. The package is in contrib because it depend on +the <a href="https://tracker.debian.org/pkg/fdk-aac">non-free fdk-aac +library</a>. The Debian package lack support for streaming web pages +because Debian is missing CEF, Chromium Embedded Framework. CEF is +wanted by several packages in Debian. But because the Chromium source +is <a href="https://bugs.debian.org/893448">not available as a build +dependency</a>, it is not yet possible to upload CEF to Debian. I +hope this will change in the future.</p> + +<p>The reason I got involved is that +<a href="https://frikanalen.no/">the Norwegian open channel +Frikanalen</a> is starting to use CasparCG for our HD playout, and I +would like to have all the free software tools we use to run the TV +channel available as packages from the Debian project. The last +remaining piece in the puzzle is Open Broadcast Encoder, but it depend +on quite a lot of patched libraries which would have to be included in +Debian first.</p> + + + Learn to program with Minetest on Debian http://people.skolelinux.org/pere/blog/Learn_to_program_with_Minetest_on_Debian.html @@ -467,112 +500,6 @@ irc.freenode.net</a>) or email (<a href="https://lists.nuug.no/mailman/listinfo/nikita-noark">nikita-noark mailing list</a>).</p> -<p>As usual, if you use Bitcoin and want to show your support of my -activities, please send Bitcoin donations to my address -<b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p> - - - - - Fetching trusted timestamps using the rfc3161ng python module - http://people.skolelinux.org/pere/blog/Fetching_trusted_timestamps_using_the_rfc3161ng_python_module.html - http://people.skolelinux.org/pere/blog/Fetching_trusted_timestamps_using_the_rfc3161ng_python_module.html - Mon, 8 Oct 2018 12:30:00 +0200 - <p>I have earlier covered the basics of trusted timestamping using the -'openssl ts' client. See blog post for -<a href="http://people.skolelinux.org/pere/blog/Public_Trusted_Timestamping_services_for_everyone.html">2014</a>, -<a href="http://people.skolelinux.org/pere/blog/syslog_trusted_timestamp___chain_of_trusted_timestamps_for_your_syslog.html">2016</a> -and -<a href="http://people.skolelinux.org/pere/blog/Idea_for_storing_trusted_timestamps_in_a_Noark_5_archive.html">2017</a> -for those stories. But some times I want to integrate the timestamping -in other code, and recently I needed to integrate it into Python. -After searching a bit, I found -<a href="https://dev.entrouvert.org/projects/python-rfc3161">the -rfc3161 library</a> which seemed like a good fit, but I soon -discovered it only worked for python version 2, and I needed something -that work with python version 3. Luckily I next came across -<a href="https://github.com/trbs/rfc3161ng/">the rfc3161ng library</a>, -a fork of the original rfc3161 library. Not only is it working with -python 3, it have fixed a few of the bugs in the original library, and -it has an active maintainer. I decided to wrap it up and make it -<a href="https://tracker.debian.org/pkg/python-rfc3161ng">available in -Debian</a>, and a few days ago it entered Debian unstable and testing.</p> - -<p>Using the library is fairly straight forward. The only slightly -problematic step is to fetch the required certificates to verify the -timestamp. For some services it is straight forward, while for others -I have not yet figured out how to do it. Here is a small standalone -code example based on of the integration tests in the library code:</p> - -<pre> -#!/usr/bin/python3 - -""" - -Python 3 script demonstrating how to use the rfc3161ng module to -get trusted timestamps. - -The license of this code is the same as the license of the rfc3161ng -library, ie MIT/BSD. - -""" - -import os -import pyasn1.codec.der -import rfc3161ng -import subprocess -import tempfile -import urllib.request - -def store(f, data): - f.write(data) - f.flush() - f.seek(0) - -def fetch(url, f=None): - response = urllib.request.urlopen(url) - data = response.read() - if f: - store(f, data) - return data - -def main(): - with tempfile.NamedTemporaryFile() as cert_f,\ - tempfile.NamedTemporaryFile() as ca_f,\ - tempfile.NamedTemporaryFile() as msg_f,\ - tempfile.NamedTemporaryFile() as tsr_f: - - # First fetch certificates used by service - certificate_data = fetch('https://freetsa.org/files/tsa.crt', cert_f) - ca_data_data = fetch('https://freetsa.org/files/cacert.pem', ca_f) - - # Then timestamp the message - timestamper = \ - rfc3161ng.RemoteTimestamper('http://freetsa.org/tsr', - certificate=certificate_data) - data = b"Python forever!\n" - tsr = timestamper(data=data, return_tsr=True) - - # Finally, convert message and response to something 'openssl ts' can verify - store(msg_f, data) - store(tsr_f, pyasn1.codec.der.encoder.encode(tsr)) - args = ["openssl", "ts", "-verify", - "-data", msg_f.name, - "-in", tsr_f.name, - "-CAfile", ca_f.name, - "-untrusted", cert_f.name] - subprocess.check_call(args) - -if '__main__' == __name__: - main() -</pre> - -<p>The code fetches the required certificates, store them as temporary -files, timestamp a simple message, store the message and timestamp to -disk and ask 'openssl ts' to verify the timestamp. A timestamp is -around 1.5 kiB in size, and should be fairly easy to store for future -use.</p> - <p>As usual, if you use Bitcoin and want to show your support of my activities, please send Bitcoin donations to my address <b><a href="bitcoin:15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b">15oWEoG9dUPovwmUL9KWAnYRtNJEkP1u1b</a></b>.</p>