CBR and bitrate

Previous Topic Next Topic
 
classic Classic list List threaded Threaded
7 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

CBR and bitrate

akash kulkarni
hello everyone

i have file with CBR and when i am converting it to other format by using
following command i am getting VBR both video and audio

ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
-b:v 25M -c:a aac ouput.MTS

so How i can get the output file in CBR mode and frame rate 25.
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: CBR and bitrate

jmkhoo1
If you mean a constant frame rate, use -r:v 25. If you actually mean bitrate, use -b:v and -b:a. I think you might want to look at the x264 switches to make sure that it is encoded and a constant bit rate, though I am fairly sure specifying a bit rate will do it.-------- Original message --------From: akash kulkarni <[hidden email]> Date: 8/10/2017  7:18 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]> Subject: [FFmpeg-user] CBR and bitrate
hello everyone

i have file with CBR and when i am converting it to other format by using
following command i am getting VBR both video and audio

ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
-b:v 25M -c:a aac ouput.MTS

so How i can get the output file in CBR mode and frame rate 25.
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: CBR and bitrate

jmkhoo1
In reply to this post by akash kulkarni
Apologies. I should have tried it out first. You are correct. Even specifying r:v and -b:v failed.-------- Original message --------From: jmkhoo1 <[hidden email]> Date: 8/10/2017  9:28 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]> Subject: Re: [FFmpeg-user] CBR and bitrate
If you mean a constant frame rate, use -r:v 25. If you actually mean bitrate, use -b:v and -b:a. I think you might want to look at the x264 switches to make sure that it is encoded and a constant bit rate, though I am fairly sure specifying a bit rate will do it.-------- Original message --------From: akash kulkarni <[hidden email]> Date: 8/10/2017  7:18 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]> Subject: [FFmpeg-user] CBR and bitrate
hello everyone

i have file with CBR and when i am converting it to other format by using
following command i am getting VBR both video and audio

ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
-b:v 25M -c:a aac ouput.MTS

so How i can get the output file in CBR mode and frame rate 25.
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: CBR and bitrate

akash kulkarni
its fine @jmkhoo1 atleast you tried and its appreciated...
input file is of constant bit rate mode after executing command i am
getting variable bit rate...
so question was how i get the CBR mode output

On Thu, Aug 10, 2017 at 7:59 PM, jmkhoo1 <[hidden email]>
wrote:

> Apologies. I should have tried it out first. You are correct. Even
> specifying r:v and -b:v failed.-------- Original message --------From:
> jmkhoo1 <[hidden email]> Date: 8/10/2017  9:28 AM
> (GMT-05:00) To: FFmpeg user questions <[hidden email]> Subject:
> Re: [FFmpeg-user] CBR and bitrate
> If you mean a constant frame rate, use -r:v 25. If you actually mean
> bitrate, use -b:v and -b:a. I think you might want to look at the x264
> switches to make sure that it is encoded and a constant bit rate, though I
> am fairly sure specifying a bit rate will do it.-------- Original message
> --------From: akash kulkarni <[hidden email]> Date: 8/10/2017
> 7:18 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]>
> Subject: [FFmpeg-user] CBR and bitrate
> hello everyone
>
> i have file with CBR and when i am converting it to other format by using
> following command i am getting VBR both video and audio
>
> ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
> -b:v 25M -c:a aac ouput.MTS
>
> so How i can get the output file in CBR mode and frame rate 25.
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
>
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: CBR and bitrate

Manuel Tiglio
I have had the same problem with both CBR and constrained VBR, even with two passes, and no luck in really controlling the bitrate as specified. I posted it a couple of weeks ago but did not get anyone who could really get CBR and or 110% or 150% or any other constrained VBR or at least exactly how to reproduce any results.


> On Aug 10, 2017, at 10:35 PM, akash kulkarni <[hidden email]> wrote:
>
> its fine @jmkhoo1 atleast you tried and its appreciated...
> input file is of constant bit rate mode after executing command i am
> getting variable bit rate...
> so question was how i get the CBR mode output
>
> On Thu, Aug 10, 2017 at 7:59 PM, jmkhoo1 <[hidden email]>
> wrote:
>
>> Apologies. I should have tried it out first. You are correct. Even
>> specifying r:v and -b:v failed.-------- Original message --------From:
>> jmkhoo1 <[hidden email]> Date: 8/10/2017  9:28 AM
>> (GMT-05:00) To: FFmpeg user questions <[hidden email]> Subject:
>> Re: [FFmpeg-user] CBR and bitrate
>> If you mean a constant frame rate, use -r:v 25. If you actually mean
>> bitrate, use -b:v and -b:a. I think you might want to look at the x264
>> switches to make sure that it is encoded and a constant bit rate, though I
>> am fairly sure specifying a bit rate will do it.-------- Original message
>> --------From: akash kulkarni <[hidden email]> Date: 8/10/2017
>> 7:18 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]>
>> Subject: [FFmpeg-user] CBR and bitrate
>> hello everyone
>>
>> i have file with CBR and when i am converting it to other format by using
>> following command i am getting VBR both video and audio
>>
>> ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
>> -b:v 25M -c:a aac ouput.MTS
>>
>> so How i can get the output file in CBR mode and frame rate 25.
>> _______________________________________________
>> ffmpeg-user mailing list
>> [hidden email]
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>
>> To unsubscribe, visit link above, or email
>> [hidden email] with subject "unsubscribe".
>> _______________________________________________
>> ffmpeg-user mailing list
>> [hidden email]
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>
>> To unsubscribe, visit link above, or email
>> [hidden email] with subject "unsubscribe".
>> _______________________________________________
>> ffmpeg-user mailing list
>> [hidden email]
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>>
>> To unsubscribe, visit link above, or email
>> [hidden email] with subject "unsubscribe".
>>
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".

_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: CBR and bitrate

akash kulkarni
yes @manuel its getting bit hard even after setting
  -b:v 25M -minrate 25M maxrate 25M -bufsize 25M it not generating CBR mode
output and i will try for 1 & 2 pass once and convey you if i get the
constrained VBR

On Fri, Aug 11, 2017 at 11:20 AM, Manuel Tiglio <[hidden email]> wrote:

> I have had the same problem with both CBR and constrained VBR, even with
> two passes, and no luck in really controlling the bitrate as specified. I
> posted it a couple of weeks ago but did not get anyone who could really get
> CBR and or 110% or 150% or any other constrained VBR or at least exactly
> how to reproduce any results.
>
>
> > On Aug 10, 2017, at 10:35 PM, akash kulkarni <[hidden email]>
> wrote:
> >
> > its fine @jmkhoo1 atleast you tried and its appreciated...
> > input file is of constant bit rate mode after executing command i am
> > getting variable bit rate...
> > so question was how i get the CBR mode output
> >
> > On Thu, Aug 10, 2017 at 7:59 PM, jmkhoo1 <jmkhoo1-at-yahoo.com@ffmpeg.
> org>
> > wrote:
> >
> >> Apologies. I should have tried it out first. You are correct. Even
> >> specifying r:v and -b:v failed.-------- Original message --------From:
> >> jmkhoo1 <[hidden email]> Date: 8/10/2017  9:28 AM
> >> (GMT-05:00) To: FFmpeg user questions <[hidden email]> Subject:
> >> Re: [FFmpeg-user] CBR and bitrate
> >> If you mean a constant frame rate, use -r:v 25. If you actually mean
> >> bitrate, use -b:v and -b:a. I think you might want to look at the x264
> >> switches to make sure that it is encoded and a constant bit rate,
> though I
> >> am fairly sure specifying a bit rate will do it.-------- Original
> message
> >> --------From: akash kulkarni <[hidden email]> Date: 8/10/2017
> >> 7:18 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]>
> >> Subject: [FFmpeg-user] CBR and bitrate
> >> hello everyone
> >>
> >> i have file with CBR and when i am converting it to other format by
> using
> >> following command i am getting VBR both video and audio
> >>
> >> ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
> >> -b:v 25M -c:a aac ouput.MTS
> >>
> >> so How i can get the output file in CBR mode and frame rate 25.
> >> _______________________________________________
> >> ffmpeg-user mailing list
> >> [hidden email]
> >> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
> >>
> >> To unsubscribe, visit link above, or email
> >> [hidden email] with subject "unsubscribe".
> >> _______________________________________________
> >> ffmpeg-user mailing list
> >> [hidden email]
> >> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
> >>
> >> To unsubscribe, visit link above, or email
> >> [hidden email] with subject "unsubscribe".
> >> _______________________________________________
> >> ffmpeg-user mailing list
> >> [hidden email]
> >> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
> >>
> >> To unsubscribe, visit link above, or email
> >> [hidden email] with subject "unsubscribe".
> >>
> > _______________________________________________
> > ffmpeg-user mailing list
> > [hidden email]
> > http://ffmpeg.org/mailman/listinfo/ffmpeg-user
> >
> > To unsubscribe, visit link above, or email
> > [hidden email] with subject "unsubscribe".
>
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
>
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: CBR and bitrate

Dragan Randjelovic
In reply to this post by jmkhoo1
use nal-hrd option:

-x264opts nal-hrd=cbr:force-cfr=1 ( -b:v 25M -minrate 25M maxrate 25M
-bufsize 25M )



*hrd=cbr*

Regards.


On Thu, Aug 10, 2017 at 3:28 PM, jmkhoo1 <[hidden email]>
wrote:

> If you mean a constant frame rate, use -r:v 25. If you actually mean
> bitrate, use -b:v and -b:a. I think you might want to look at the x264
> switches to make sure that it is encoded and a constant bit rate, though I
> am fairly sure specifying a bit rate will do it.-------- Original message
> --------From: akash kulkarni <[hidden email]> Date: 8/10/2017
> 7:18 AM  (GMT-05:00) To: FFmpeg user questions <[hidden email]>
> Subject: [FFmpeg-user] CBR and bitrate
> hello everyone
>
> i have file with CBR and when i am converting it to other format by using
> following command i am getting VBR both video and audio
>
> ffmpeg -i input.mp4 -y -r 25 -c:v libx264 -look_ahead 0 -preset veryfast
> -b:v 25M -c:a aac ouput.MTS
>
> so How i can get the output file in CBR mode and frame rate 25.
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
> _______________________________________________
> ffmpeg-user mailing list
> [hidden email]
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>
> To unsubscribe, visit link above, or email
> [hidden email] with subject "unsubscribe".
>
_______________________________________________
ffmpeg-user mailing list
[hidden email]
http://ffmpeg.org/mailman/listinfo/ffmpeg-user

To unsubscribe, visit link above, or email
[hidden email] with subject "unsubscribe".
Loading...