Hello all,
I'm developing an industrial application using the Galaxy Camera: basically, the camera is connected to a PC through an USB cable, and is used as a remotely controlled picture camera.
What I have to do is control the camera from the PC, play live preview on the PC and take pictures.
I developed a server application on the camera side which communicates, through several sockets and ports with the PC over the USB, with the help of the ADB program.
On the PC side a C# client plays the live preview, control the camera and takes the nedeed pictures.
Using Android APIs and camera parameters I'm able to control everything I need on the camera.
However, I'm facing a big problem now: while the camera is running, connected to the PC and streaming live preview to it, the camera power consumption is so high I cannot hold the battery charger (the conversion process from raw preview to Jpeg -YuvImage.CompressToJpg- is really CPU loading, and the USB current is too low); so, every time, after few hours, I end up with a discharged battery.
This is not acceptable, cause my customers will use the camera for continuous working flow, even for several days.
The problem is that when the Camera is connected to an USB plug the charging current is automatically limited, to avoid to overload the computer USB port.
There's a way to force the charging process to use high current even with an USB connection to a PC (simulating AC charge), but doing so USB communication will be lost, interrupting the communication between the camera and the PC.
In other word, if you want a USB connection to a PC, you'll have a low charging current; if you want an high charging current, you loose the USB connectivity!
This is not an hardware problem, but a Kernel limitation (as far as I've understood).
So, my question is: would it be possible to modify the Kernel in manner to add the possibility to charge the camera as fast as wee can (AC charge), while mantaining USB communication?
How? Where?
I read many and many post on various forums, but I didn't undertand it could be done or not, and how.
I'm running Android 4.1.2, Kernel version 3.0.31 - 751817 (if this could be useful).
Please help me!
Thank you in advance.
Regards,
Giovanni
I think this can be changed in the Kernel settings.
Maybe it helps to ask Andip:
http://forum.xda-developers.com/showthread.php?t=1964572
gronph said:
I think this can be changed in the Kernel settings.
Maybe it helps to ask Andip:
http://forum.xda-developers.com/showthread.php?t=1964572
Click to expand...
Click to collapse
It requires changes to the kernel to support the setting, but if going to the SIII forum, asking a developer how to add it, getting the source, adding it in, and compiling makes more sense than checking out our own kernel thread and just saying "can that be next?", then by all means...
Sent from my EK-GC110 using Tapatalk 4
twistedumbrella said:
It requires changes to the kernel to support the setting, but if going to the SIII forum, asking a developer how to add it, getting the source, adding it in, and compiling makes more sense than checking out our own kernel thread and just saying "can that be next?", then by all means...
Sent from my EK-GC110 using Tapatalk 4
Click to expand...
Click to collapse
Thank you for your answer, but, due to the fact English is not my native language, your statement is not completely clear to me.
Are you suggesting me to log into the Galaxy Camera Kernel thread (where is it? I can't find it) and ask for a new feature?
Is there any programmer that is working on the Kernel?
Please address me to any useful link, please.
Ciao,
Giovanni
croccodillo said:
Thank you for your answer, but, due to the fact English is not my native language, your statement is not completely clear to me.
Are you suggesting me to log into the Galaxy Camera Kernel thread (where is it? I can't find it) and ask for a new feature?
Is there any programmer that is working on the Kernel?
Please address me to any useful link, please.
Ciao,
Giovanni
Click to expand...
Click to collapse
Most of that was not directed at you. I didn't see a purpose in sending someone to the SIII when we do have a custom kernel here. I will be adding fast charge to it shortly.
http://forum.xda-developers.com/showpost.php?p=44040889
croccodillo said:
Thank you for your answer, but, due to the fact English is not my native language, your statement is not completely clear to me.
Are you suggesting me to log into the Galaxy Camera Kernel thread (where is it? I can't find it) and ask for a new feature?
Is there any programmer that is working on the Kernel?
Please address me to any useful link, please.
Ciao,
Giovanni
Click to expand...
Click to collapse
Here you are the Adam Kernel sources (for GT-I9300), wich has usb fast charge feature. You can build your kernel simply merging the right code from this source to your own galaxy camera source, since the two devices have the same chipset.
https://github.com/wanam/Adam-Kernel-GS3
Correct me if I'm wrong
I think I see why this forum saw so little traffic before. Each thread is an island, forced to fend for itself with only the SIII to assist it.
Delux9364 said:
Here you are the Adam Kernel sources (for GT-I9300), wich has usb fast charge feature. You can build your kernel simply merging the right code from this source to your own galaxy camera source, since the two devices have the same chipset.
https://github.com/wanam/Adam-Kernel-GS3
Correct me if I'm wrong
Click to expand...
Click to collapse
Doesn't include it as anything that can be extracted.
twistedumbrella said:
Doesn't include it as anything that can be extracted.
Click to expand...
Click to collapse
what do u mean?
Delux9364 said:
what do u mean?
Click to expand...
Click to collapse
A commit, a comment, a function with a name that indicates that is what it does.
From everything i've seen the fast charge patch was only made for msm and omap kernels. This one may require going about it differently.
Sent from my Galaxy Nexus using Tapatalk 2
twistedumbrella said:
A commit, a comment, a function with a name that indicates that is what it does.
From everything i've seen the fast charge patch was only made for msm and omap kernels. This one may require going about it differently.
Sent from my Galaxy Nexus using Tapatalk 2
Click to expand...
Click to collapse
what about Siyah Kernel for i9300?
Delux9364 said:
what about Siyah Kernel for i9300?
Click to expand...
Click to collapse
Strike two...
twistedumbrella said:
Strike two...
Click to expand...
Click to collapse
Please be more clear when you write something, as many of ours don't speak English as current language.
Again: what do you mean?
Delux9364 said:
Please be more clear when you write something, as many of ours don't speak English as current language.
Again: what do you mean?
Click to expand...
Click to collapse
Do you have baseball where you are from?
https://www.google.com/#q=strike+two
First search result:
http://idioms.thefreedictionary.com/two+strikes+against
Google is your friend.
This device forum is not large like the others, so being lazy does not help what little development we have going here.
Related
Is there a mini USB to HDMI ...... MHL (Mobile High-Definition Link) adapter available to connect Touchpad to TV ?
or what is the best method you guys using to connect Touchpad to TV
dellxda said:
Is there a mini USB to HDMI ...... MHL (Mobile High-Definition Link) adapter available to connect Touchpad to TV ?
or what is the best method you guys using to connect Touchpad to TV
Click to expand...
Click to collapse
I know there are USB-HDMI cables, but what kind of pinout connections for the TP translate?
The TP plug LOOKS like the one on my Samsung Mythic phone cable, but I sure as hell wouldn't plug it in!
Pros to why it might work
The chipset is capable
It doesn't appear that HP messed with the reference design
Cons to why it might not work
Chipset may be capable but no idea if the drivers to do it are in WebOS
It could have been removed
I can't find if anyone has tried an MHL adapter on the Touchpad yet
I've yet to hear of anyone outputting any video with the touchpad to an external screen.
I tried an MHL adaptor on the touchpad and it doesn't work.
Would be good if there's any other way to link it to a TV/Monitor.
DavidMc0 said:
I tried an MHL adaptor on the touchpad and it doesn't work.
Click to expand...
Click to collapse
Confirmed
Too51oll said:
Confirmed
Click to expand...
Click to collapse
So now the question is, is it because the hardware was modified or is it lacking in the software?
Another thought I had was looking to Bluetooth VDP support. Since WebOS uses the bluez stack and there was some work previously on VDP for bluez it shouldn't be too hard to the profile working. There is also the SPP video approach however both of these would need one to have a Bluetooth receiver to display the video.
Shelnutt2 said:
So now the question is, is it because the hardware was modified or is it lacking in the software?
Click to expand...
Click to collapse
Regardless of whether or not the hardware supports it, the software definitely does not.
CyanogenMod team is investigating as part of Android port for HP Touchpad
http://code.google.com/p/cmtouchpad/issues/detail?id=38
Maybe in 3.04?
nToxik said:
Maybe in 3.04?
Click to expand...
Click to collapse
I wouldn't get my hopes up given the state of WebOS. Android is looking like the best solution right now especially with ICS just around the corner.
gentleman, it WILL NOT work on 3.0.2 or 3.0.3, but is the #1 feature for 3.0.4, so either wait for that, or hope that CM team gets it working, but it prolly wont work in CM7 1.0 as its not the most important thing to have working at launch
luisdg said:
I wouldn't get my hopes up given the state of WebOS. Android is looking like the best solution right now especially with ICS just around the corner.
Click to expand...
Click to collapse
Actually, I understood HDMI-out was confirmed to be part of 3.0.4.
Really, HP has nothing to gain by holding out on us, so I can't imagine they would.
Solidus_n313 said:
gentleman, it ... is the #1 feature for 3.0.4
Click to expand...
Click to collapse
...source?
scrizz said:
...source?
Click to expand...
Click to collapse
CM, but Dalingrin more specifically. He says it is supported by the SoC, pinouts are the big question.
Google it or search here at xda. The phrase "webos 3.0.4 hdmi" worked for me.
nunjabusiness said:
CM, but Dalingrin more specifically. He says it is supported by the SoC, pinouts are the big question.
Google it or search here at xda. The phrase "webos 3.0.4 hdmi" worked for me.
Click to expand...
Click to collapse
he meant source for "gentleman, it ... is the #1 feature for 3.0.4"... is it actually official or just people on the forum mentioning it? i only seen mostly user statements that hdmi out will be on 3.0.4.. nothing offficial
edit: is webos 3.0.3 out? i am on 3.0.2 and went to system updates but it says i am on latest version
yeahman45 said:
he meant source for "gentleman, it ... is the #1 feature for 3.0.4"... is it actually official or just people on the forum mentioning it? i only seen mostly user statements that hdmi out will be on 3.0.4.. nothing offficial
edit: is webos 3.0.3 out? i am on 3.0.2 and went to system updates but it says i am on latest version
Click to expand...
Click to collapse
source is from HP devs, im looking for the link in my history (EDIT: dammit, link is pulled, HP is cracking down on these leaks hard. looking for cached page)
as for 3.0.3, it WAS available, but HP sent a C&D to xda and nbournes (something like that, my bad ) so its gone, and HP also deactivated the dev reg server, so you have to impostah bypass to use 3.0.3, you get the camera app, faster browser but no access to app catalog or HP resources
luisdg said:
I wouldn't get my hopes up given the state of WebOS. Android is looking like the best solution right now especially with ICS just around the corner.
Click to expand...
Click to collapse
I very much doubt they will add ANY new features,and any in the works will probably be removed or disabled in the final release. I think HP is releasing one last software update to deal with the fact that the software that shipped is junk. Its slow and buggy and I think HP feels that they need to fix the outstanding issues. I seriously doubt they feel they need to put any energy into adding new features. WebOS IS dead. Hp is not making devices running it anymore and no one is going to want it. They may be able to sell it for a few bucks to someone who wants the palm patent portfolio though. At the right price google might want those patents. The idea that HP will keep flushing money down the webOS hole though is absurd.
gentleman, it WILL NOT work on 3.0.2 or 3.0.3, but is the #1 feature for 3.0.4, so either wait for that, or hope that CM team gets it working, but it prolly wont work in CM7 1.0 as its not the most important thing to have working at launch
Click to expand...
Click to collapse
That is still great news.
well some bad news is that i cant find the post ANYWHERE :/ so take it as a grain of salt if you want, but either way, we're getting hdmi out eventually
Solidus_n313 said:
but no access to app catalog or HP resources
Click to expand...
Click to collapse
there is HP app catalog access....
you just have to follow all the directions.
and since there is No Proof that HDMI is the #1 feature of 3.0.4, I'm calling BS until there is proof.
Hi
I've had a single sitting around for awhile and I've learnt that you can get a xoom to use this via a USB cable, I've found support for it on honeycomb but nothing about ics yet, is it too early.
Anyone know of any topics for this.
Thanks
gmonkeyuk said:
Hi
I've had a single sitting around for awhile and I've learnt that you can get a xoom to use this via a USB cable, I've found support for it on honeycomb but nothing about ics yet, is it too early.
Anyone know of any topics for this.
Thanks
Click to expand...
Click to collapse
Provide specific details on make, model, and chipset. Then I can compile a driver.
bigrushdog said:
Provide specific details on make, model, and chipset. Then I can compile a driver.
Click to expand...
Click to collapse
UK Wifi mZ604 wingray, Nightly build 54 Timat kernel 3.0.4 ICS 4.0.3
If need more info just ask. Thanks
bigrushdog said:
Provide specific details on make, model, and chipset. Then I can compile a driver.
Click to expand...
Click to collapse
BRD, is the requisite driver (option/sierra) all that's necessary to use one of those to get on-line? Are there any user-space (Android/Framework) changes necessary as well?
kcrudup said:
BRD, is the requisite driver (option/sierra) all that's necessary to use one of those to get on-line? Are there any user-space (Android/Framework) changes necessary as well?
Click to expand...
Click to collapse
I've never played with one, so I'm only going off what Ive read. Should be the same as the Ethernet dongles. Create the interface, register with dhcp if need be, etc. However, there is user-space work that needs to be done for all of these interface mods. Most people report limited functionality as many apps don't "see" the interface. So I believe there are some extra unknown steps. I'm gonna start a fresh thread on this topic because it seems to be a popular concept. I'll holla
bigrushdog said:
Should be the same as the Ethernet dongles. ... Most people report limited functionality as many apps don't "see" the interface. ...
Click to expand...
Click to collapse
I'm gonna bet that's even just as simple as using an "iface=" parameter on the command line (or fixing it up in code).
I'm gonna start a fresh thread on this topic because it seems to be a popular concept. I'll holla
Click to expand...
Click to collapse
Yeah- 'cause as we've discussed in private, what I'd like to be able to do is replace my internal LTE Mini-PCI modem with one of the HSDPA+ Mini-PCI modems I've got lying around, so when I travel overseas I can use my Xoom with native GSM 3G data.
The third version of this connector will have it's own power source. So stay tune.
Update: version v.2
Instructions here.
Did you really need to spam these images all over the forums? post them once and the link to them if you must, after checking that your mod would actually be of use to the device whose forum you're posting in. The otg might work on a rooted N7 like yours but it's no good for the One S.
Troute said:
Did you really need to spam these images all over the forums? post them once and the link to them if you must, after checking that your mod would actually be of use to the device whose forum you're posting in. The otg might work on a rooted N7 like yours but it's no good for the One S.
Click to expand...
Click to collapse
Ok done. It won't work for One S? I don't see why not. But let me check. Sorry about this, only meant to help.
Edit: So, it'll work if it has it's own power source. I'm going to make a power source on v.2 soon for you guys. Stay tune.
Cheers
USB OTG works on AOKP without a power source.
Darknites said:
USB OTG works on AOKP without a power source.
Click to expand...
Click to collapse
Great! Update: version v.2
Capt.PP said:
Great! Update: version v.2
Click to expand...
Click to collapse
That's really cool. Thanks for the effort but I use this $0.80 cable adapter and it works just fine. No power needed with CM10. What's the point of DIY if the alternative is 80 cents? I'm really really not trying to thread crap I just don't get it.
http://www.amazon.com/T-Flash-Adapter-Samsung-GT-i9100-GT-N7000/dp/B005FUNYSA/ref=sr_1_2?ie=UTF8&qid=1353398912&sr=8-2&keywords=otg+cable
Also your thread title says GUILD not GUIDE.
dc211 said:
That's really cool. Thanks for the effort but I use this $0.80 cable adapter and it works just fine. No power needed with CM10. What's the point of DIY if the alternative is 80 cents? I'm really really not trying to thread crap I just don't get it.
http://www.amazon.com/T-Flash-Adapter-Samsung-GT-i9100-GT-N7000/dp/B005FUNYSA/ref=sr_1_2?ie=UTF8&qid=1353398912&sr=8-2&keywords=otg+cable
Also your thread title says GUILD not GUIDE.
Click to expand...
Click to collapse
Oh thanks, I'm really tire. Smallest form factor to prevent accident and obstruction. The best of all, the fun to mod.
Yeah but when the right way to do it is available commercially, then it just too much trouble and people run the risk of shorting out pins on their phones. Thread closed.
As the title said, is this phone support it?
this is the only feature i'm waiting to decide if i'll buy this
grimmyrippy said:
As the title said, is this phone support it?
this is the only feature i'm waiting to decide if i'll buy this
Click to expand...
Click to collapse
LG has resolved the power issue, so it should. Recall that the N4 was released as USB OTG, but had to be backtracked when it was discovered there was no power. Fortunately,,cable and kernel tweaks by devs worked around the issue.
wideasleep1 said:
LG has resolved the power issue, so it should. Recall that the N4 was released as USB OTG, but had to be backtracked when it was discovered there was no power. Fortunately,,cable and kernel tweaks by devs worked around the issue.
Click to expand...
Click to collapse
YAAAAY!!!
Looks like it should from the various log file leaks etc. My main reservation will be the ability to get ethernet working OTG like with the N7. Got this working with my Note2 after building the kernel modules myself - hopefully the N5 will be precompiled, or easy to create too.
Most Android phones at the moment support it so it would be weird if the N5 didn't support it
ehcool said:
Most Android phones at the moment support it so it would be weird if the N5 didn't support it
Click to expand...
Click to collapse
maybe for making it cheap xD
If the service manual that was leaked is accurate, the hardware will support USB OTG. There are a bunch of references in the manual (the Qualcomm power management IC has a VOUT_5VS_OTG output, a block diagram for the charging/USB area shows +5V0_OTG_OVP (over voltage protection), and there is a OTG enable line listed (OTG_EN)).
I didn't realize the N4 didn't support OTG (without a bit of a work around) until I came across this thread and did some reading about it.
Matt
mtucker said:
If the service manual that was leaked is accurate, the hardware will support USB OTG. There are a bunch of references in the manual (the Qualcomm power management IC has a VOUT_5VS_OTG output, a block diagram for the charging/USB area shows +5V0_OTG_OVP (over voltage protection), and there is a OTG enable line listed (OTG_EN)).
I didn't realize the N4 didn't support OTG (without a bit of a work around) until I came across this thread and did some reading about it.
Matt
Click to expand...
Click to collapse
this weekend i will order this:good::good::good::good::good::fingers-crossed::fingers-crossed::fingers-crossed:
http://www.meenova.com/
danmaman said:
this weekend i will order this:good::good::good::good::good::fingers-crossed::fingers-crossed::fingers-crossed:
http://www.meenova.com/
Click to expand...
Click to collapse
That is a nifty device. I was going to sell my 64GB uSD card with my Note2 after I get the Nexus 5, but maybe I will hang on to it and get one those uSD adapters. It would be much easier to carry that uSD adapter with a 64GB card inside instead of an OTG cable and a thumb drive.
Matt
If the N5 is even loosely based on the LG G2 it will have USB OTG host. My G2 natively mounts mass storage devices via USB OTG.
Does any one have a link to a mirror of the N5 service manual?
Sent from my VS980 4G using xda app-developers app
ElecEngineer1422 said:
.........Does any one have a link to a mirror of the N5 service manual?
Click to expand...
Click to collapse
I had a hard time finding it, but eventually I Googled lg-D821.pdf and found this...... ironically stored on Google Docs. You will get a warning about the file being too big for Google to virus check it. I went for it and it is the manual.
https://docs.google.com/file/d/0B7VNhP6LbXNmdl9wZG1OSTBnVUE/edit?usp=sharing
mtucker said:
I had a hard time finding it, but eventually I Googled lg-D821.pdf and found this...... ironically stored on Google Docs. You will get a warning about the file being too big for Google to virus check it. I went for it and it is the manual.
https://docs.google.com/file/d/0B7VNhP6LbXNmdl9wZG1OSTBnVUE/edit?usp=sharing
Click to expand...
Click to collapse
Nice! Thanks for this!
hi, I read that google now ("ok google") only activates when the screen is on. I was wondering if theres a hack or setting somewhere where you can activate it with the screen off? I mostly want this for hands-free use in the car, so I can avoid having to touch the phone while driving (big no no).
also, is there a site somewhere explaining all the features of what you can say/ask google now? or even a link with comparisons between siri and google now, and what google now cant do that siri does? I ask this cuz ill be coming from iPhone.
thanks.
I think that would really drain the battery - if possible!
However, here is a collection on some of the commands you can ask google now:
http://forum.xda-developers.com/showthread.php?t=1961636
I'm really surprised how great it works! And i live in Denmark, where i can't even take full use of everything
samsung has had this with s-voice. and i think motorola enabled google now to do this on the motox but i'm not sure. yes it drains battery, but how much? depends on the cpu and driver and the software involved..... i don't have my nexus yet so i can't say "how" to do this but i would expect it to be an eventual custom feature if not a future update if it's not already in a setting somewhere.
reffer2 said:
I think that would really drain the battery - if possible!
However, here is a collection on some of the commands you can ask google now:
http://forum.xda-developers.com/showthread.php?t=1961636
I'm really surprised how great it works! And i live in Denmark, where i can't even take full use of everything
Click to expand...
Click to collapse
Everything I've read has claimed that the Nexus 5 should handle this as well as MotoX since it has the Snapdragon 800. Have we ever gotten an official answer on why this won't work?
reffer2 said:
I think that would really drain the battery - if possible!
However, here is a collection on some of the commands you can ask google now:
http://forum.xda-developers.com/showthread.php?t=1961636
I'm really surprised how great it works! And i live in Denmark, where i can't even take full use of everything
Click to expand...
Click to collapse
hey thanks for the link. battery drain wouldn't be too much of an issue, as usually I would just use it while the device is being charged in my car, but it would be nice to use sometimes without as well, and while leaving the screen on would be nice, a slow charging car charger, is going to charge faster with the screen off, as that's usually the most power hungry lol. so it would be nice to have the voice activation at will while using.
If some of the launcher/search code was open source, I'd imagine this would be quite easy to do.
Pretty sure I read somewhere that the 'always listening' (for "OK Google" command) requires some hardware functionality. So no, it would not be possible like it is on the Moto X.
bbedward said:
If some of the launcher/search code was open source, I'd imagine this would be quite easy to do.
Click to expand...
Click to collapse
i'd imagine you could port parts of the moto x rom into the nexus. things like this have been done before. just have to find all the dependancies.
Dani897 said:
i'd imagine you could port parts of the moto x rom into the nexus. things like this have been done before. just have to find all the dependancies.
Click to expand...
Click to collapse
I mean, if you had access to the facilities used by the n5 launcher source, you could likely utilize them when screen is off via software pretty easily.
Sent from my Nexus 5 using Tapatalk
akhan47 said:
Pretty sure I read somewhere that the 'always listening' (for "OK Google" command) requires some hardware functionality. So no, it would not be possible like it is on the Moto X.
Click to expand...
Click to collapse
Yes. But from what I understand the snapdragon 800 has that hardware built in.
Sent from my Nexus 5 using Tapatalk
http://www.qualcomm.com/snapdragon/processors/800
Video is about 1/2 way down on the right. Processor is capable.
Lets see if I can't clear things up. If you want your phone to be always listening, you need hardware support for it unless you want your phone to die in a matter of hours. If you are okay with this , check out this app. https://play.google.com/store/apps/details?id=com.RSen.OpenMic.Pheonix It also lets you configure things like only when charging or just when the screen is on to save some battery, and its actually a very nice app overall. Worth checking out.
The Moto x has a special custom chip set that allows for this always listening. Any attempt to port that feature from the Moto x would fail, as the Nexus 5 doesn't have the same chip set. The nexus 5 however, does have hardware that allows for always listening, its part of the Snapdragon 800 SOC that powers this phone, along with the Note 3 and LG G2.
But getting the feature to actually work on our phones, even with the hardware, is by no means an easy task. Read the comments on this post if you want to get an idea for what this entails. https://plus.google.com/112424215551484520138/posts/AznwFxbBapJ
So is it possible? Yes. But it is not something that is gonna be a quick easy port of small modification of an existing app, it would take some real serious work form (maybe a team even of) good Dev's to make this function.
Sorry if its not the news you wanted to hear.
Well now it's been more than a year since this thread is dead but i bought my N5 recently and i wonder is there any progress in this matter will it be possible ? (G+ comments on link provided by above like shows it may be possible...as SD800 has privilege for it but at time of this thread it was only available to OMEs so it made public yet ? ) . did any dev tried to dig into this matter ?
jineshpatel30 said:
Well now it's been more than a year since this thread is dead but i bought my N5 recently and i wonder is there any progress in this matter will it be possible ? (G+ comments on link provided by above like shows it may be possible...as SD800 has privilege for it but at time of this thread it was only available to OMEs so it made public yet ? ) . did any dev tried to dig into this matter ?
Click to expand...
Click to collapse
It won't happen on an N5 . ?
Darth said:
It won't happen on an N5 . ?
Click to expand...
Click to collapse
that's sad but okay ! what else we can say
If you're plugged in/wireless charging Google Now Voice commands work with the screen off.
Settings>Language & Input > Voice Input> Enhanced Google services> "OK Google" Detection>From any screen> enabled
"responds to your voice. Works when the screen is on or the device is charging."
make sure the next option "personal results" is also enabled if you want Google Now to be able to do anything
Try this app, Open Mic+. It'll do the job.