is it possible to split two channel (stereo) ?

karthiiivgn commented 6 years ago

hi i'm using audiowaveform its good for getting audio wavform.

i have stereo audio to be displayed in two waveform graph (left-right channels). is it possible?

example link: https://wavesurfer-js.org/examples/ see the Split channels

chrisn commented 6 years ago

This isn't currently supported, but I'm open to adding this as a new feature.

To do this, we'll need to define a new version of the dat and JSON formats to support multiple channels. This should be a straightforward extension of the existing formats, with the version field incremented to 2, add a channel count field to the header, and then store the waveform data interleaved like this:

    min value, index 0, channel 0
    max value, index 0, channel 0
    min value, index 0, channel 1
    max value, index 0, channel 1
    min value, index 1, channel 0
    max value, index 1, channel 0
    min value, index 1, channel 1
    max value, index 1, channel 1

etc.

This would mean that libraries that consume this data would need to be updated (waveform-data.js and Peaks.js primarily).

karthiiivgn commented 6 years ago

Thanks for your quick response... I am looking foreword for your feature

karthiiivgn commented 6 years ago

I'm proud of your efficient work. Thanks for giving solution when i got the two channel, i am expect two wave graph lines.

crx-gus commented 6 years ago

Hey Chris - seconded. We would love to be able to generate a two channel waveform!

Vijayalaxmim commented 6 years ago

Hey Chris, is this feature supported ,because I do not see anything in docs .My request is to view 2 channel waveforms separately instead of one in stereotype audio.

chrisn commented 6 years ago

Hi @Vijayalaxmim. This feature is not currently supported, I plan to come back to it after the next couple of weeks.

chrisn commented 6 years ago

Here's my current thinking on how this feature will work:

There will be a new --split-channels command line option, to enable multiple channel output files.
For backwards compatibility, if you don't specify --split-channels, the output will be the same as it is now, with all input channels merged into a single waveform. Files will continue to use the existing version 1 format.
When generating waveform data (binary or JSON format), if you specify --split-channels, and if the input has more than one channel, the output file will be the new version 2, as described above, and will contain a waveform per channel. For compatibility purposes, if the input has only one channel, the output file will continue to use the version 1 format.
When generating PNG files, if you specify --split-channels, the output image will show all channels from the input file, one above the other, similar to the example mentioned above.
At a later date, I may consider adding a --channel option that allows you to select a single channel for the output waveform data or image file from an input file with multiple channels.

chrisn commented 6 years ago

The --split-channels option is in release 1.3.0.

crx-gus commented 6 years ago

Awesome work! Thanks.

Gus Sharples, Senior Solutions Architect CR-X Pty Ltd BIG DATA INTEGRATION

email: gus.sharples@cr-x.com phone: +61 3 9828 <//+61 3 9828> 9153 mobile: +61 415 313 <//+61 415 313> 228

On 22 November 2018 at 8:15:34 pm, Chris Needham (notifications@github.com) wrote:

The --split-chanels option is in release 1.3.0.

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karthiiivgn commented 6 years ago

Great!,

I'm using older version 1.2.0 how to upgrade this

chrisn commented 6 years ago

I suggest holding off testing 1.3 for now, I'm not happy with the new v2 header format. I'll publish a version 1.3.2 shortly to fix it.

chrisn commented 6 years ago

Version 1.3.2 is now available.

@karthiiivgn On Ubuntu, you can install from my PPA, or on a Mac you can install via Homebrew. Anything else would require building from source. Details are in the README. Please let me know if this feature works for you, feedback welcome.

karthiparthi commented 3 weeks ago

hi i'm using audiowaveform its good for getting audio wavform.

i have stereo audio to be displayed in two waveform graph (left-right channels). is it possible?

example link: https://wavesurfer-js.org/examples/ see the Split channels

This will work

bbc / audiowaveform

is it possible to split two channel (stereo) ? #73