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Hello Carl,<br>
<br>
Thanks for the response !<br>
<br>
<blockquote type="cite">
<pre wrap="">Yes, there is no free lunch.
You will have to find values that work for you and are smaller than
the default.</pre>
</blockquote>
The problem is that I'm working with a RTP multicast streams; not
static files. So what I see happening a lot is the following:<br>
<br>
<ul>
<li>I set values that are smaller than the default</li>
<li>The values work in most cases; however some times they do not.
When this happens; what is the best course of action ? Can I
just increase the values and try again without wasting too much
time ?</li>
</ul>
<p> </p>
<blockquote type="cite">
<pre wrap="">How do you know you have gathered "all the basic information" of
a transport stream?
(There was a sample stream for which -probesize 2G was not enough
so we increased the range for the option.)</pre>
</blockquote>
I guess I could have been clearer, sorry. What I meant was; is there
a way of telling FFMPEG to imminently stop analyzing the stream
(even if the "probesize" number of bytes haven't been used up yet)
once it gathers enough information about the stream ?<br>
<p>So for instance if the <b>probesize </b>is set to 4MB; if my
understanding is correct FFMPEG will finish
avformat_find_stream_info/avfromat_open_input only when it reads
all 4MB of data. Isn't there a way to stop it from reading the
rest if for instance, only 1MB was enough to get the metadata from
the stream ?</p>
<p>So I guess what I'm trying to say is; I would like it to stop
analyzing the stream:<br>
</p>
<ul>
<li>In case of audio, as soon as it detects the codec type, sample
rate and number of channels.</li>
<li>In case of video, as soon as it detects the codec type, video
resolution and "extradata" in case of H264/H265<br>
</li>
</ul>
<p>Best regards,<br>
Nikola<br>
</p>
<br>
<div class="moz-cite-prefix">On 17-May-17 10:05, Carl Eugen Hoyos
wrote:<br>
</div>
<blockquote
cite="mid:CAB0OVGp5N4yXkXPJkat6Fbp=gP4sEnHif_G=JU9kHAXxjxRS2Q@mail.gmail.com"
type="cite">
<pre wrap="">2017-05-15 11:09 GMT+02:00 Nikola Spiric <a class="moz-txt-link-rfc2396E" href="mailto:nikola.spiric.ns@gmail.com"><nikola.spiric.ns@gmail.com></a>:
</pre>
<blockquote type="cite">
<pre wrap="">I tried reducing "probesize" and "analyzeduration" parameters with
mixed results. Sometimes it indeed does speed up mentioned function
calls; however they often just result in the functions failing (i.e. they
don't get enough data to provide me with all the information I need).
</pre>
</blockquote>
<pre wrap="">Yes, there is no free lunch.
You will have to find values that work for you and are smaller than
the default.
</pre>
<blockquote type="cite">
<pre wrap="">So my question is: Is there a way to tell FFMPEG to stop analyzing the
stream once it gathers all the basic information (video width/height,
h.264/HEVC extra data or audio sample rate/number of channels) ?
</pre>
</blockquote>
<pre wrap="">How do you know you have gathered "all the basic information" of
a transport stream?
(There was a sample stream for which -probesize 2G was not enough
so we increased the range for the option.)
</pre>
<blockquote type="cite">
<pre wrap="">I really need a way of speeding up these two function calls (5
seconds is not acceptable for my needs).
</pre>
</blockquote>
<pre wrap="">5 seconds seem extremely long on current hardware.
Carl Eugen
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</pre>
</blockquote>
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