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by czar1na
Fri Mar 24, 2017 10:41 pm
Forum: Beginners
Topic: Using mmap in Raspbian?
Replies: 4
Views: 929

Using mmap in Raspbian?

Hi, I'm running a Pi Zero, Raspbian Jessie. I'm looking for a way to write/read data from memory with a very large buffer. I need to use memory rather than disk because I'm reading/writing in real-time and speed is important. I'm currently using a FIFO pipe, but it has an upper buffer-size limit of ...
by czar1na
Fri Mar 24, 2017 5:44 am
Forum: Troubleshooting
Topic: How to add timestamps to video/audio in realtime?
Replies: 0
Views: 445

How to add timestamps to video/audio in realtime?

Hi, I am livestreaming audio and video from a Pi Zero, and I need to add timestamps to both, based off 1 master clock, so I can keep them in sync. I can't figure out how to add SoC timestamps to either video or audio in real-time. 1. I am trying raspivid -pts option and mkvmerge to add TS to the vid...
by czar1na
Thu Mar 02, 2017 2:34 pm
Forum: Beginners
Topic: Smallest 4g dongle?
Replies: 7
Views: 7917

Re: Smallest 4g dongle?

It's the equivalent of eg your Verizon Jetpack. Designed to allow you to tether mobile devices & enjoy the 4G connection. The same "mobile hotspot" I suggested ;) Tethering to a 4G Verizon Jetpack is my current plan, but the major US carriers' "unlimited" plans all allow for only ~10GB of tethered ...
by czar1na
Thu Mar 02, 2017 2:15 pm
Forum: Beginners
Topic: Smallest 4g dongle?
Replies: 7
Views: 7917

Re: Smallest 4g dongle?

I am in the UK, Three Mobile offer a 3G/4G Huawei Mobile WiFi Router with a Data Plan. The Huawei E5573 Mobile WiFi Router is Battery Powered and charged via a USB Cable, when connected to a RPi by USB Cable enumerates as an Internet Connection: http://www.three.co.uk/Discover/Devices/Huawei/E5573_...
by czar1na
Thu Mar 02, 2017 12:54 am
Forum: Beginners
Topic: Smallest 4g dongle?
Replies: 7
Views: 7917

Smallest 4g dongle?

Hi all, Some of you may have read my threads about my project, which is to build a live streaming necklace from a Pi Zero. I do now have my pi zero set up to stream video and audio to the internet. However, my pi is connected via wifi to my phone and relying on my phone's data to send the stream. Th...
by czar1na
Tue Feb 28, 2017 10:37 pm
Forum: Beginners
Topic: Any improvements to my setup's power management?
Replies: 0
Views: 294

Any improvements to my setup's power management?

Hey guys, I'm building a portable Zero device that I want to run as long as possible in between charges. I'm trying to look for optimizations that can decrease my power consumption by >1%. I'll describe my setup and what I've already done: - Pi Zero, running Jessie headlessly. Its HDMI port is disab...
by czar1na
Tue Feb 28, 2017 5:06 pm
Forum: Graphics, sound and multimedia
Topic: Running Pi cam at 1.0004x speed?
Replies: 3
Views: 805

Re: Running Pi cam at 1.0004x speed?

I've answered this question numerous times - use timestamps. Any two clocks will drift, so something has to be treated as a master clock with timestamps slaved off that. The camera frame time also has to be a multiple of the line time (between 17 and 33ns depending on sensor and readout mode). See ...
by czar1na
Tue Feb 28, 2017 1:55 am
Forum: Graphics, sound and multimedia
Topic: Running Pi cam at 1.0004x speed?
Replies: 3
Views: 805

Running Pi cam at 1.0004x speed?

Sorry for the barrage of q's. As some of you may have read in my other thread, I'm livestreaming video+audio from my Pi Zero, Pi v2 Camera, and MEMS mic to Youtube. I've discovered that while the audio+video in my stream starts out perfectly synced, they desync at a very consistent pace as time goes...
by czar1na
Mon Feb 27, 2017 6:18 pm
Forum: Graphics, sound and multimedia
Topic: A few q's about quantisation in raspivid?
Replies: 5
Views: 1746

Re: A few q's about quantisation in raspivid?

I'm reading the firmware source code. Any codec implementation will have some design decisions, hence I always go to the source for Pi as that is the platform I'm supporting. Thanks, this makes a lot of sense. Sorry for the stupid question, but if the logic raspivid uses is in the h264 encoder soft...
by czar1na
Mon Feb 27, 2017 5:31 pm
Forum: Graphics, sound and multimedia
Topic: A few q's about quantisation in raspivid?
Replies: 5
Views: 1746

Re: A few q's about quantisation in raspivid?

Thanks for the reply! What bitrate have you requested? Is there any detail at all in the scene when it drops to 600kbit/s? There are limits to the QP that rate control will turn it up to, so pictures of black cats on dark nights do tend to hit the extremes. I have not requested any bitrate/compressi...
by czar1na
Mon Feb 27, 2017 4:19 pm
Forum: Graphics, sound and multimedia
Topic: A few q's about quantisation in raspivid?
Replies: 5
Views: 1746

A few q's about quantisation in raspivid?

Hi, I'm streaming video from my Pi Zero, using raspivid (h264 encoded video) ->ffmpeg (copy and mux with audio) ->Youtube Live. I'm using 720p@25FPS, which I have specified in the raspivid command. I've noticed that at this constant resolution and FPS, and 1.0x speed (realtime streaming), some of my...
by czar1na
Mon Feb 27, 2017 1:09 pm
Forum: Troubleshooting
Topic: Raspberry pi camera with purple bands, static?
Replies: 5
Views: 1038

Re: Raspberry pi camera with purple bands, static?

jamesh wrote:It's a push fit on the board, get a finger nail under it and gentry prise it off, then reseat with a small amount of pressure - it will click in to place.
Seemed to do the trick, at least for now, thank you!
by czar1na
Mon Feb 27, 2017 12:58 pm
Forum: Troubleshooting
Topic: Raspberry pi camera with purple bands, static?
Replies: 5
Views: 1038

Re: Raspberry pi camera with purple bands, static?

Same issue as here: https://www.raspberrypi.org/forums/viewtopic.php?f=43&t=172974&p=1106766&hilit=purple#p1106766 ? Did you re-seat that Sunny connector? It's the tiny one on the camera PCB. Flip it up and pop it back in place. Any better? Oh, I see. Don't see a label for a Sunny connector but wou...
by czar1na
Mon Feb 27, 2017 12:28 pm
Forum: Troubleshooting
Topic: Raspberry pi camera with purple bands, static?
Replies: 5
Views: 1038

Re: Raspberry pi camera with purple bands, static?

Ever since I placed my Pi camera+ribbon inside a velvet cloth band for several days last week, I've only been able to use the camera successfully about 50% of the time. I've already removed the device from the cloth band and store it in an electrostatic-safe baggie now. When it works, the camera is ...
by czar1na
Mon Feb 27, 2017 6:20 am
Forum: Troubleshooting
Topic: How to maximize USB wifi dongle speeds?
Replies: 2
Views: 593

How to maximize USB wifi dongle speeds?

I have a Pi Zero and a Edimax EW-7811Un 150Mbps USB wifi dongle: https://www.amazon.com/Edimax-EW-7811Un-150Mbps-Raspberry-Supports/dp/B003MTTJOY I'm powering my Pi with a 1000C Powerboost and 1200Mah li-po battery. Nothing is currently running on it, but there are a Pi camera and a MEMS mic attache...
by czar1na
Sat Feb 25, 2017 2:07 pm
Forum: General discussion
Topic: Be careful with Pi Zero and CSI slot
Replies: 40
Views: 11720

Re: Be careful with Pi Zero and CSI slot

I just tried the CSI slot on another PI Zero, and it is MUCH tighter and easier to use than the one on my current main Zero. So I've realized the issue is that I opened and closed the CSI slot on my Zero so many times that it got very loose. Bit of advice for others that it shouldn't be as bad as I ...
by czar1na
Sat Feb 25, 2017 3:31 am
Forum: Troubleshooting
Topic: Raspberry pi camera with purple bands, static?
Replies: 5
Views: 1038

Raspberry pi camera with purple bands, static?

image.jpg Recently my Pi cam v2 has taken images like these, with purple and static bands in them. I'm wondering if something has damaged my camera. I have placed my camera and the camera ribbon inside a velvet cloth band that sometimes sheds fibers, and I've read that they are sensitive to static ...
by czar1na
Sat Feb 25, 2017 2:14 am
Forum: Troubleshooting
Topic: USB wifi dongle TP-LINK not recognized?
Replies: 0
Views: 253

USB wifi dongle TP-LINK not recognized?

16933922_10212168543315241_1295287501_n.jpg Hi, I have bought a TP-LINK micro USB wifi dongle for my Pi Zero. I stripped it out of its case to save space, and soldered it directly onto the test pads like here: https://www.raspberrypi.org/forums/viewtopic.php?f=63&t=127449 I've tested the 4 connecti...
by czar1na
Fri Feb 24, 2017 7:49 am
Forum: General discussion
Topic: Be careful with Pi Zero and CSI slot
Replies: 40
Views: 11720

Re: Be careful with Pi Zero and CSI slot

I'd be wary of daubing that stuff over the connector & cable until I'd explored other, more easily reversible, options. Like running tape down the back of the ribbon & on to the back of the PCB, same repeated best you can top side. You could also design your case such that it pinches the ribbon whe...
by czar1na
Fri Feb 24, 2017 5:08 am
Forum: General discussion
Topic: Be careful with Pi Zero and CSI slot
Replies: 40
Views: 11720

Re: Be careful with Pi Zero and CSI slot

test.jpg I have to say, I've probably had to re-insert the ribbon into the Zero's CSI slot many hundreds of times over the course of my project, it is so incredibly easy to come loose and so difficult to secure. It seems to work exactly opposite from how you would hope. When I pull it open, the sli...
by czar1na
Wed Feb 22, 2017 9:01 pm
Forum: Camera board
Topic: New 8MP Camera - Q&A thread
Replies: 450
Views: 195153

Re: New 8MP Camera - Q&A thread

But also considering 3D printing my own wrench.... I had my wrench printed from a publicly available STL file by a maker located nearby (using 3Dhubs). It isn't really a perfect fit, I guess due to the home-3D-print accuracy, but it did the job - I just had to hold it under small angle in order to ...
by czar1na
Wed Feb 22, 2017 3:29 pm
Forum: Camera board
Topic: New 8MP Camera - Q&A thread
Replies: 450
Views: 195153

Re: New 8MP Camera - Q&A thread

Still wondering if anyone wants to sell me their spanner (I am in California, US) But also considering 3D printing my own wrench from the shared file. I do have access to a 3D printer, though I've never used it before. I'm trying to figure out how difficult all of this is, as I'm not the handiest an...
by czar1na
Wed Feb 22, 2017 5:51 am
Forum: Camera board
Topic: New 8MP Camera - Q&A thread
Replies: 450
Views: 195153

Re: New 8MP Camera - Q&A thread

Hi all,

I have a V2 Pi camera which seems out of focus. Mine didn't seem to ship with that plastic white knob that helps you adjust the focus. Does anyone have a spare one that I could buy off of you?
by czar1na
Wed Feb 22, 2017 3:48 am
Forum: Troubleshooting
Topic: Trying to understand basics of bitrate, FPS, speed?
Replies: 1
Views: 637

Trying to understand basics of bitrate, FPS, speed?

Hi, I have a pretty simple question. I'm streaming audio and video from my Pi Zero using a combination of raspivid (video), sox (audio), and ffmpeg (muxing+streaming). My Pi has a wifi module and I'm getting 5Mbps max upload speed based on a speed-cli test. If I use 640x480p, 10FPS, and 500kbps vide...
by czar1na
Wed Feb 22, 2017 3:31 am
Forum: Beginners
Topic: Camera out of focus?
Replies: 1
Views: 461

Camera out of focus?

Hi,

I have a Pi V2 Camera. I took a sample photo with it using 'raspistill -o test.jpg'; here is the result: http://imgur.com/a/VJtMX

It looks really blurry. Is it possible my camera is out of focus?

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