linux-media.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux.
@ 2014-04-23 15:22 Steve Cookson
  2014-04-25 12:19 ` Steve Cookson
  0 siblings, 1 reply; 5+ messages in thread
From: Steve Cookson @ 2014-04-23 15:22 UTC (permalink / raw)
  To: Linux Media Mailing List

Hi Guys,

I would be interested in your views of the comparisons of these images.  
The still is the image of a duodenum taken during an endoscopy and 
recorded to a DVD player (via an s-video or composite cable).  Although 
the endoscope is an HD endoscope, the DVD recorder isn't and the 
resulting video is 720x480i59.94.

Here are further details of the video:-

Format : MPEG Video v2
Format profile : Main@Main
Format settings, BVOP : Yes, Matrix : Custom, GOP : M=3, N=15
Bit rate mode : Variable
Bit rate : 4 566 Kbps
Maximum bit rate : 10 000 Kbps
Width : 720 pixels
Height : 480 pixels
Display aspect ratio : 4:3
Frame rate : 29.970 fps
Standard : NTSC
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Interlaced
Scan order : Top Field First
Compression mode : Lossy
Bits/(Pixel*Frame) : 0.441

The video was played through Dragon Player and the video signal has 
exited through a mini-VGA port defined as 640x480 and passed through a 
VGA->S-Video converter to an s-video cable.

The cable has in turn been connected in turn to a Dazzle DVC100, an 
EasyCap stk1160 and a Hauppauge ImapctVCB-e.

Each setting (eg brightness and contrast etc) has as near as possible to 
mid-range and a screengrab taken.

The results are shown here:

Original: 
http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMrgmD6gSf74Ih4l5k2TGxc

Dazzle DVC100: 
http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMaOf4QTsIefYh4l5k2TGxc

ImpactVCB-e: 
http://tinypic.com/usermedia.php?uo=fNkd6hpTbcM7i72IqGujuIh4l5k2TGxc

STK1160: 
http://tinypic.com/usermedia.php?uo=fNkd6hpTbcPO7kmQk/IS94h4l5k2TGxc

I would be grateful for your views on the quality of the images.

Is one of materially higher quality than the others, or can I adjust the 
settings to improve the quality of one of them more.

It seems to me that the Hauppauge is marginally better than the others.  
What do you think?

Can I improve the test?

Regards

Steve.




^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux.
  2014-04-23 15:22 Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux Steve Cookson
@ 2014-04-25 12:19 ` Steve Cookson
       [not found]   ` <CALzAhNWvQ1ZYL-0rK2w7yPwzm9QyyCN8JvRyjGhq5eO6rOH9dw@mail.gmail.com>
  2014-04-25 13:26   ` Ezequiel Garcia
  0 siblings, 2 replies; 5+ messages in thread
From: Steve Cookson @ 2014-04-25 12:19 UTC (permalink / raw)
  To: Steve Cookson, Linux Media Mailing List, Steven Toth, Hans Verkuil
  Cc: ezequiel.garcia

Hi Guys,

(I'm copying Ezequial on this because of the work he has done on the 
stk1160).

My colleague (a Doctor) had this to say on the medical images I posted 
earlier (see below):

 >  The impactVCB-e image is redder and less clear. The dvc100 and 
easycap seem similar to me and both of them are not as good as the 
original one.

So I have to ask how is it that the cheap little EasyCap is performing 
at the same level as the Dazzle DVC100 and better than the ImpactVCB-e?

It seems to me that the more complex and expensive DVC100 and 
ImpactVCB-e should perform well and that the EasyCap should be the 
runner up.

If the DVC100 and ImpactVCB-e had had the same love and attention that 
Ezequial has shown the EasyCap would they outperform it?

The ImpactVCB-e is easier to use internally and the Dazzle is external.  
Does the fact that the ImpactVCB-e has a PCI-e connector help it at all?

Otherwise I should just focus on EasyCap for my raw SD capture and move on.

Thanks,

Steve


On 23/04/14 16:22, Steve Cookson wrote:
> Hi Guys,
>
> I would be interested in your views of the comparisons of these 
> images.  The still is the image of a duodenum taken during an 
> endoscopy and recorded to a DVD player (via an s-video or composite 
> cable).  Although the endoscope is an HD endoscope, the DVD recorder 
> isn't and the resulting video is 720x480i59.94.
>
> Here are further details of the video:-
>
> Format : MPEG Video v2
> Format profile : Main@Main
> Format settings, BVOP : Yes, Matrix : Custom, GOP : M=3, N=15
> Bit rate mode : Variable
> Bit rate : 4 566 Kbps
> Maximum bit rate : 10 000 Kbps
> Width : 720 pixels
> Height : 480 pixels
> Display aspect ratio : 4:3
> Frame rate : 29.970 fps
> Standard : NTSC
> Color space : YUV
> Chroma subsampling : 4:2:0
> Bit depth : 8 bits
> Scan type : Interlaced
> Scan order : Top Field First
> Compression mode : Lossy
> Bits/(Pixel*Frame) : 0.441
>
> The video was played through Dragon Player and the video signal has 
> exited through a mini-VGA port defined as 640x480 and passed through a 
> VGA->S-Video converter to an s-video cable.
>
> The cable has in turn been connected in turn to a Dazzle DVC100, an 
> EasyCap stk1160 and a Hauppauge ImapctVCB-e.
>
> Each setting (eg brightness and contrast etc) has as near as possible 
> to mid-range and a screengrab taken.
>
> The results are shown here:
>
> Original: 
> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMrgmD6gSf74Ih4l5k2TGxc
>
> Dazzle DVC100: 
> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMaOf4QTsIefYh4l5k2TGxc
>
> ImpactVCB-e: 
> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcM7i72IqGujuIh4l5k2TGxc
>
> STK1160: 
> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcPO7kmQk/IS94h4l5k2TGxc
>
> I would be grateful for your views on the quality of the images.
>
> Is one of materially higher quality than the others, or can I adjust 
> the settings to improve the quality of one of them more.
>
> It seems to me that the Hauppauge is marginally better than the 
> others.  What do you think?
>
> Can I improve the test?
>
> Regards
>
> Steve.
>
>
>
> -- 
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux.
       [not found]   ` <CALzAhNWvQ1ZYL-0rK2w7yPwzm9QyyCN8JvRyjGhq5eO6rOH9dw@mail.gmail.com>
@ 2014-04-25 12:48     ` Steven Toth
  2014-04-25 12:59       ` Hans Verkuil
  0 siblings, 1 reply; 5+ messages in thread
From: Steven Toth @ 2014-04-25 12:48 UTC (permalink / raw)
  To: Steve Cookson
  Cc: Steve Cookson, Linux Media Mailing List, Hans Verkuil, ezequiel.garcia

Doh, HTML cause vger to drop it. Resending.

On Fri, Apr 25, 2014 at 8:47 AM, Steven Toth <stoth@kernellabs.com> wrote:
> On Fri, Apr 25, 2014 at 8:19 AM, Steve Cookson <it@sca-uk.com> wrote:
>>
>> Hi Guys,
>>
>
> Hello again.
>
>>
>> (I'm copying Ezequial on this because of the work he has done on the
>> stk1160).
>>
>> My colleague (a Doctor) had this to say on the medical images I posted
>> earlier (see below):
>>
>> >  The impactVCB-e image is redder and less clear. The dvc100 and easycap
>> > seem similar to me and both of them are not as good as the original one.
>>
>> So I have to ask how is it that the cheap little EasyCap is performing at
>> the same level as the Dazzle DVC100 and better than the ImpactVCB-e?
>>
>
> Its usually either because the Linux engineers simply aren't focused on
> improving quality for the last 'mile', or that the ADC/Video digitizer
> differers between products. 'Redder' isn't usually a differentiation between
> video digitizer silicon, its miss-configuration - for example.
>
>
>>
>> It seems to me that the more complex and expensive DVC100 and ImpactVCB-e
>> should perform well and that the EasyCap should be the runner up.
>>
>
> Not necessarily, but I can understand why you may think that. The reality is
> - you are measuring the work of individuals who we're not paid to create
> these Linux drivers. They work well enough for their needs, they scratched
> their own itch, then they moved on, more than likely this is the case. So,
> you are seeing a mixture of different silicon, different attention to
> detail, different default values and different levels of commitment in the
> driver developers.
>
>> If the DVC100 and ImpactVCB-e had had the same love and attention that
>> Ezequial has shown the EasyCap would they outperform it?
>>
>
> Hard to say. With my experience working for Hauppauge, directly in their
> engineering team, having worked on literally hundreds of products, lots of
> different video digitizer, they're all fairly close quality wise in general,
> with good signals, with the right drivers.
>
> What makes a good video digitizer stand out from a poor one, it how it
> performs in very poor signal conditions.
>
>
>>
>> The ImpactVCB-e is easier to use internally and the Dazzle is external.
>> Does the fact that the ImpactVCB-e has a PCI-e connector help it at all?
>>
>
>
> Invariably not.
>
>
>>
>> Otherwise I should just focus on EasyCap for my raw SD capture and move
>> on.
>>
>
> You need to make that judgement call. If you are building a business around
> medical imaging and have no engineering capability to improve drivers, go
> with what your gut says and what's available to you today. You shouldn't
> rely on the good will of Linux engineers to fix your business requirements
> in their spare time, in the coming weeks or months.
>
> Or, hire a consultant to improve the drivers for you and the rest of the
> Linux community. This what everyone else does.
>
> - Steve
>
>>
>> Thanks,
>>
>> Steve
>>
>>
>> On 23/04/14 16:22, Steve Cookson wrote:
>>>
>>> Hi Guys,
>>>
>>> I would be interested in your views of the comparisons of these images.
>>> The still is the image of a duodenum taken during an endoscopy and recorded
>>> to a DVD player (via an s-video or composite cable).  Although the endoscope
>>> is an HD endoscope, the DVD recorder isn't and the resulting video is
>>> 720x480i59.94.
>>>
>>> Here are further details of the video:-
>>>
>>> Format : MPEG Video v2
>>> Format profile : Main@Main
>>> Format settings, BVOP : Yes, Matrix : Custom, GOP : M=3, N=15
>>> Bit rate mode : Variable
>>> Bit rate : 4 566 Kbps
>>> Maximum bit rate : 10 000 Kbps
>>> Width : 720 pixels
>>> Height : 480 pixels
>>> Display aspect ratio : 4:3
>>> Frame rate : 29.970 fps
>>> Standard : NTSC
>>> Color space : YUV
>>> Chroma subsampling : 4:2:0
>>> Bit depth : 8 bits
>>> Scan type : Interlaced
>>> Scan order : Top Field First
>>> Compression mode : Lossy
>>> Bits/(Pixel*Frame) : 0.441
>>>
>>> The video was played through Dragon Player and the video signal has
>>> exited through a mini-VGA port defined as 640x480 and passed through a
>>> VGA->S-Video converter to an s-video cable.
>>>
>>> The cable has in turn been connected in turn to a Dazzle DVC100, an
>>> EasyCap stk1160 and a Hauppauge ImapctVCB-e.
>>>
>>> Each setting (eg brightness and contrast etc) has as near as possible to
>>> mid-range and a screengrab taken.
>>>
>>> The results are shown here:
>>>
>>> Original:
>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMrgmD6gSf74Ih4l5k2TGxc
>>>
>>> Dazzle DVC100:
>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMaOf4QTsIefYh4l5k2TGxc
>>>
>>> ImpactVCB-e:
>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcM7i72IqGujuIh4l5k2TGxc
>>>
>>> STK1160:
>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcPO7kmQk/IS94h4l5k2TGxc
>>>
>>> I would be grateful for your views on the quality of the images.
>>>
>>> Is one of materially higher quality than the others, or can I adjust the
>>> settings to improve the quality of one of them more.
>>>
>>> It seems to me that the Hauppauge is marginally better than the others.
>>> What do you think?
>>>
>>> Can I improve the test?
>>>
>>> Regards
>>>
>>> Steve.
>>>
>>>
>>>
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-media" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>
>>
>
>
>
> --
> Steven Toth - Kernel Labs
> http://www.kernellabs.com
>



-- 
Steven Toth - Kernel Labs
http://www.kernellabs.com
+1.646.355.8490

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux.
  2014-04-25 12:48     ` Steven Toth
@ 2014-04-25 12:59       ` Hans Verkuil
  0 siblings, 0 replies; 5+ messages in thread
From: Hans Verkuil @ 2014-04-25 12:59 UTC (permalink / raw)
  To: Steve Cookson, Steve Cookson
  Cc: Steven Toth, Linux Media Mailing List, ezequiel.garcia

I looked at the pictures as well and I noticed a few things:

The aspect ratio of the impactvcb-e isn't right, it's too narrow. What width
and height did you specify when capturing? I can't test this myself as I'm
abroad, but try 720x480 or 768x480.

I also noticed that the cx23885 driver selects slightly incorrect default
brightness, contrast and saturation values. Whether that is the cause of the
color differences is debatable, but you can try using my repo:

git://linuxtv.org/hverkuil/media_tree.git

Checkout the cx23 branch.

This branch contains a pile of cleanup patches including a conversion to the
control framework, which should ensure correct (to my knowledge) defaults for
the color controls.

Regards,

	Hans

On 04/25/2014 02:48 PM, Steven Toth wrote:
> Doh, HTML cause vger to drop it. Resending.
> 
> On Fri, Apr 25, 2014 at 8:47 AM, Steven Toth <stoth@kernellabs.com> wrote:
>> On Fri, Apr 25, 2014 at 8:19 AM, Steve Cookson <it@sca-uk.com> wrote:
>>>
>>> Hi Guys,
>>>
>>
>> Hello again.
>>
>>>
>>> (I'm copying Ezequial on this because of the work he has done on the
>>> stk1160).
>>>
>>> My colleague (a Doctor) had this to say on the medical images I posted
>>> earlier (see below):
>>>
>>>>  The impactVCB-e image is redder and less clear. The dvc100 and easycap
>>>> seem similar to me and both of them are not as good as the original one.
>>>
>>> So I have to ask how is it that the cheap little EasyCap is performing at
>>> the same level as the Dazzle DVC100 and better than the ImpactVCB-e?
>>>
>>
>> Its usually either because the Linux engineers simply aren't focused on
>> improving quality for the last 'mile', or that the ADC/Video digitizer
>> differers between products. 'Redder' isn't usually a differentiation between
>> video digitizer silicon, its miss-configuration - for example.
>>
>>
>>>
>>> It seems to me that the more complex and expensive DVC100 and ImpactVCB-e
>>> should perform well and that the EasyCap should be the runner up.
>>>
>>
>> Not necessarily, but I can understand why you may think that. The reality is
>> - you are measuring the work of individuals who we're not paid to create
>> these Linux drivers. They work well enough for their needs, they scratched
>> their own itch, then they moved on, more than likely this is the case. So,
>> you are seeing a mixture of different silicon, different attention to
>> detail, different default values and different levels of commitment in the
>> driver developers.
>>
>>> If the DVC100 and ImpactVCB-e had had the same love and attention that
>>> Ezequial has shown the EasyCap would they outperform it?
>>>
>>
>> Hard to say. With my experience working for Hauppauge, directly in their
>> engineering team, having worked on literally hundreds of products, lots of
>> different video digitizer, they're all fairly close quality wise in general,
>> with good signals, with the right drivers.
>>
>> What makes a good video digitizer stand out from a poor one, it how it
>> performs in very poor signal conditions.
>>
>>
>>>
>>> The ImpactVCB-e is easier to use internally and the Dazzle is external.
>>> Does the fact that the ImpactVCB-e has a PCI-e connector help it at all?
>>>
>>
>>
>> Invariably not.
>>
>>
>>>
>>> Otherwise I should just focus on EasyCap for my raw SD capture and move
>>> on.
>>>
>>
>> You need to make that judgement call. If you are building a business around
>> medical imaging and have no engineering capability to improve drivers, go
>> with what your gut says and what's available to you today. You shouldn't
>> rely on the good will of Linux engineers to fix your business requirements
>> in their spare time, in the coming weeks or months.
>>
>> Or, hire a consultant to improve the drivers for you and the rest of the
>> Linux community. This what everyone else does.
>>
>> - Steve
>>
>>>
>>> Thanks,
>>>
>>> Steve
>>>
>>>
>>> On 23/04/14 16:22, Steve Cookson wrote:
>>>>
>>>> Hi Guys,
>>>>
>>>> I would be interested in your views of the comparisons of these images.
>>>> The still is the image of a duodenum taken during an endoscopy and recorded
>>>> to a DVD player (via an s-video or composite cable).  Although the endoscope
>>>> is an HD endoscope, the DVD recorder isn't and the resulting video is
>>>> 720x480i59.94.
>>>>
>>>> Here are further details of the video:-
>>>>
>>>> Format : MPEG Video v2
>>>> Format profile : Main@Main
>>>> Format settings, BVOP : Yes, Matrix : Custom, GOP : M=3, N=15
>>>> Bit rate mode : Variable
>>>> Bit rate : 4 566 Kbps
>>>> Maximum bit rate : 10 000 Kbps
>>>> Width : 720 pixels
>>>> Height : 480 pixels
>>>> Display aspect ratio : 4:3
>>>> Frame rate : 29.970 fps
>>>> Standard : NTSC
>>>> Color space : YUV
>>>> Chroma subsampling : 4:2:0
>>>> Bit depth : 8 bits
>>>> Scan type : Interlaced
>>>> Scan order : Top Field First
>>>> Compression mode : Lossy
>>>> Bits/(Pixel*Frame) : 0.441
>>>>
>>>> The video was played through Dragon Player and the video signal has
>>>> exited through a mini-VGA port defined as 640x480 and passed through a
>>>> VGA->S-Video converter to an s-video cable.
>>>>
>>>> The cable has in turn been connected in turn to a Dazzle DVC100, an
>>>> EasyCap stk1160 and a Hauppauge ImapctVCB-e.
>>>>
>>>> Each setting (eg brightness and contrast etc) has as near as possible to
>>>> mid-range and a screengrab taken.
>>>>
>>>> The results are shown here:
>>>>
>>>> Original:
>>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMrgmD6gSf74Ih4l5k2TGxc
>>>>
>>>> Dazzle DVC100:
>>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcMaOf4QTsIefYh4l5k2TGxc
>>>>
>>>> ImpactVCB-e:
>>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcM7i72IqGujuIh4l5k2TGxc
>>>>
>>>> STK1160:
>>>> http://tinypic.com/usermedia.php?uo=fNkd6hpTbcPO7kmQk/IS94h4l5k2TGxc
>>>>
>>>> I would be grateful for your views on the quality of the images.
>>>>
>>>> Is one of materially higher quality than the others, or can I adjust the
>>>> settings to improve the quality of one of them more.
>>>>
>>>> It seems to me that the Hauppauge is marginally better than the others.
>>>> What do you think?
>>>>
>>>> Can I improve the test?
>>>>
>>>> Regards
>>>>
>>>> Steve.
>>>>
>>>>
>>>>
>>>> --
>>>> To unsubscribe from this list: send the line "unsubscribe linux-media" in
>>>> the body of a message to majordomo@vger.kernel.org
>>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>>>>
>>>
>>
>>
>>
>> --
>> Steven Toth - Kernel Labs
>> http://www.kernellabs.com
>>
> 
> 
> 

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux.
  2014-04-25 12:19 ` Steve Cookson
       [not found]   ` <CALzAhNWvQ1ZYL-0rK2w7yPwzm9QyyCN8JvRyjGhq5eO6rOH9dw@mail.gmail.com>
@ 2014-04-25 13:26   ` Ezequiel Garcia
  1 sibling, 0 replies; 5+ messages in thread
From: Ezequiel Garcia @ 2014-04-25 13:26 UTC (permalink / raw)
  To: Steve Cookson
  Cc: Steve Cookson, Linux Media Mailing List, Steven Toth, Hans Verkuil

On Apr 25, Steve Cookson wrote:
[..]
> 
> If the DVC100 and ImpactVCB-e had had the same love and attention that
> Ezequial has shown the EasyCap would they outperform it?
> 

I really appreciate the kind words and I'm happy to see the driver is being
used and works well.

However, to be fair, the stk1160 is just a little link in a larger chain.
The video decoder is controlled through another driver (saa7115) and so
I've little merit in the image quality.

[..]
> 
> Otherwise I should just focus on EasyCap for my raw SD capture and move on.
> 

Hm.. hard to say. Easycap stk1160 devices are hard to get, it seems they are
manufactured in a few different hardware flavors (but with the same case)
and it's hard to tell what flavor you buy.

Right now, I think we've supported the two stk1160 cases, but there's a
third Easycap variant currently unsupported (which doesn't use stk1160
but a Somagic chipset).

In addition, given the stk1160 was partly reverse-engineered, partly
based on a non-public and very laconic datasheet, it's not easy to fix
given the lack of details about the chip.

In conclusion, if you pick stk1160, make sure you buy enough Easycap devices
(from the same provider) and do some extra effort to test *each* of them to
ensure they work as you expect.
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2014-04-25 13:26 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-04-23 15:22 Comparisons of images between Dazzle DVC100, EasyCap stk1160 and Hauppauge ImapctVCB-e in Linux Steve Cookson
2014-04-25 12:19 ` Steve Cookson
     [not found]   ` <CALzAhNWvQ1ZYL-0rK2w7yPwzm9QyyCN8JvRyjGhq5eO6rOH9dw@mail.gmail.com>
2014-04-25 12:48     ` Steven Toth
2014-04-25 12:59       ` Hans Verkuil
2014-04-25 13:26   ` Ezequiel Garcia

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).