[EMBOSS] ABI to FASTQ with seqret

Peter biopython at maubp.freeserve.co.uk
Thu Apr 22 15:06:27 UTC 2010


On Tue, Mar 30, 2010 at 2:56 PM, Peter <biopython at maubp.freeserve.co.uk> wrote:
> On Tue, Mar 30, 2010 at 2:25 PM, Peter Rice <pmr at ebi.ac.uk> wrote:
>>
>> On 30/03/2010 14:13, Peter Rice wrote:
>>
>>> Where do I look to find scores that we can use (and how do we convert
>>> those to phred quality scores)?
>>
>> Aha, found something. The field is called PCON (confidence values), with
>> values 0-255.
>>
>> There is a possibility that these could be phred scores, but I suspect they
>> are whatever the basecaller has decided to write there.
>>
>> http://www.appliedbiosystems.com/support/software_community/ABIF_File_Format.pdf
>>
>> Peter R.
>
> Hmm. Good question - I don't know, although if they are PHRED scores
> they could go unusually high (we'd expect say 0 to 50 for a raw read).
> It could be some other encoding (e.g. scaled from 0 for a poor base to
> 255 for a perfect base). Do you have any contacts at Applied Biosystems
> to ask?
>
> Peter C.
>

Hello again Peter R (& everyone else at EMBOSS),

Did you manage to find out if the PCON confidence values in ABI files
are PHRED quality scores or not?

Regards,

Peter C.



More information about the EMBOSS mailing list