question about modifying frame rate metadata

Discussion:

nojoke68 nokoke

18 years ago

Hi -- I have some FLV files that have an incorrect frame rate.
The frame rate is 20 but it should be 5.

Is it possible to inject new metadata into the FLV file to correct this?

I.e. I want to make the framerate 4, and perhaps I have to also change the duration of the video from 129.075 to four times that, since the video will get longer.

Is this possible with this tool?

I would try it but there is no example of what syntax to use to overwrite existing metadata,
and the wiki appears to be down.

Johann

p.s. below is the current metadata

<?xml version="1.0" encoding="UTF-8"?>
<root>
<duration>129.075</duration>
<lasttimestamp>129.075</lasttimestamp>
<videocodecid>2</videocodecid>
<audiocodecid>5</audiocodecid>
<audiodelay>0</audiodelay>
<canSeekToEnd>false</canSeekToEnd>
<width>320</width>
<height>240</height>
<videodatarate>0</videodatarate>
<audiodatarate>0</audiodatarate>
<framerate>20</framerate>
<creationdate>unknown</creationdate>
<metadatacreator>Manitu Group FLV MetaData Injector 2</metadatacreator>
<metadatadate>4/18/2007 1:53:37 PM GMT-0500</metadatadate>
<videosize>3306104</videosize>
<audiosize>620993</audiosize>
<datasize>2111</datasize>
<filesize>3929221</filesize>
</root>

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nojoke68 nokoke

18 years ago

Permalink

Brooks Andrus

18 years ago

Permalink

http://www.brooksandrus.com/blog/2007/04/15/change-insert-flv-metadata-values-timestamp-dimensions-with-flvtool2/

you should be able to overwrite the metadata values without issue,
although its unclear how that will impact the playback of the video.

Brooks

...

nojoke68 nokoke

18 years ago

Permalink

Brooks --
First of all, thanks...
I was using just flvtool2 -P, I did not realize I needed to do -PU.

However it didn't work!
When I ran flvtool2 -PU -framerate:5 file.flv

it changed the framerate all right, but flvtool2 calculated other things like keyframe data and the videodatarate tag and added these to the metadata.

I thought I was able to change the videodatarate from 2000.12 to 400 and slow the file down but I can't seem to replicate this success.

question: does flvtool2 always add keyframe data?
question: anyone have any success with slowing a file down this way?
question: if it cant be done this way, what can I do to reencode it to slow it down and preserve the audio data too?

Johann
Message: 8
Date: Wed, 18 Apr 2007 11:08:50 -0700 (PDT)
From: nojoke68 nokoke
Subject: [FLVTool2-users] question about modifying frame rate metadata
To: flvtool2-***@rubyforge.org
Message-ID: <***@web32907.mail.mud.yahoo.com>
Content-Type: text/plain; charset="iso-8859-1"

Hi -- I have some FLV files that have an incorrect frame rate.
The frame rate is 20 but it should be 5.

Is it possible to inject new metadata into the FLV file to correct this?

Message: 9
Date: Wed, 18 Apr 2007 14:59:46 -0400
From: Brooks Andrus

Subject: Re: [FLVTool2-users] question about modifying frame rate
metadata
To: flvtool2-***@rubyforge.org
Message-ID: <***@gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

http://www.brooksandrus.com/blog/2007/04/15/change-insert-flv-metadata-values-timestamp-dimensions-with-flvtool2/

you should be able to overwrite the metadata values without issue,
although its unclear how that will impact the playback of the video.

Brooks

---------------------------------
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leolea

18 years ago

Permalink

Do you mean that it is possible to change de keyframe interval in a FLV
using flvtool2 ?

If so, how ??

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