Question / Help Can't capture from two USB inputs simultaneously

zelda448

New Member
Hey all,

We're trying to set up OBS to stream our Zelda marathon next month, which entails capturing from a USB Logitech C525 webcam and an Elgato video capture device (also USB) simultaneously. Unfortunately, it seems we're unable to capture from both at the same time. For example, if I make two scenes, and place the webcam in one and the Elgato in the other, then as I switch back and forth between the two, I can see both feeds just fine. However, as soon as I start to try to put both inputs in the same scene, only one of the sources will be shown.

It seems as though the computer is only accepting one video input at a time, either from the webcam or the Elgato, but never both. Both inputs work fine individually (tested via Skype for webcam and Elgato video capture software for the Elgato).

Any ideas of how to get both video sources working simultaneously?

If this has been posted elsewhere, please direct me toward it, but I have searched for this problem and haven't found it posted before.

Thanks for all your help!
 

zelda448

New Member
The computer we're using has 8-10 USB ports (2.0 and 3.0), and we've tried using a handful of them and gotten the same results will all of them. Below is a paste of the log created when I recreated the issue this morning. You can see the webcam get added (it worked fine), and then the Elgato (it didn't, no video or audio). Then I created the second scene and added the elgato to that, and it worked as we expected.

Thanks for your help.

Code:
10:16:40: Open Broadcaster Software v0.584b - 64bit ( ^ω^)
10:16:40: -------------------------------
10:16:40: CPU Name: Intel(R) Core(TM) i5-2500K CPU @ 3.30GHz
10:16:40: CPU Speed: 3292MHz
10:16:40: Physical Memory:  8174MB Total, 6754MB Free
10:16:40: stepping id: 7, model 42, family 6, type 0, extmodel 1, extfamily 0, HTT 1, logical cores 4, total cores 4
10:16:40: monitor 1: pos={0, 0}, size={1920, 1080}
10:16:40: Windows Version: 6.1 Build 7601 S
10:16:40: Aero is Enabled
10:16:40: -------------------------------
10:16:40: OBS Modules:
10:16:40: Base Address     Module
10:16:40: 000000003F570000 OBS.exe
10:16:40: 00000000DE0D0000 OBSApi.dll
10:16:40: 00000000DE090000 DShowPlugin.dll
10:16:40: 00000000DE060000 GraphicsCapture.dll
10:16:40: 00000000DE040000 NoiseGate.dll
10:16:40: 00000000DE020000 PSVPlugin.dll
10:16:40: ------------------------------------------
10:16:40: Adapter 1
10:16:40:   Video Adapter: AMD Radeon HD 6900 Series
10:16:40:   Video Adapter Dedicated Video Memory: 2134573056
10:16:40:   Video Adapter Shared System Memory: 4017451008
10:16:40:   Video Adapter Output 1: pos={0, 0}, size={1920, 1080}, attached=true
10:16:40: =====Stream Start: 2013-11-28, 10:16:40===============================================
10:16:40:   Multithreaded optimizations: On
10:16:40:   Base resolution: 1920x1080
10:16:40:   Output resolution: 1920x1080
10:16:40: ------------------------------------------
10:16:40: Loading up D3D10 on AMD Radeon HD 6900 Series...
10:16:40: ------------------------------------------
10:16:40: Audio Format: 48000hz
10:16:40: Playback device Default
10:16:40: ------------------------------------------
10:16:40: Using desktop audio input: Realtek Digital Output (Realtek High Definition Audio)
10:16:40: ------------------------------------------
10:16:40: Using auxilary audio input: Microphone (2- USB audio CODEC)
10:16:40: ------------------------------------------
10:16:40: Audio Encoding: AAC
10:16:40:     bitrate: 128
10:16:40: ------------------------------------------
10:16:40:     device: HD Webcam C525,
10:16:40:     device id \\?\usb#vid_046d&pid_0826&mi_02#7&182d5b53&0&0002#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\global,
10:16:40:     chosen type: MJPG, usingFourCC: false, res: 1920x1080 - 1920x1080, frameIntervals: 333333-2000000
10:16:40:     use buffering: false - 0, fourCC: 'MJPG'
10:16:40:     audio device: Disable,
10:16:40:     audio device id Disabled,
10:16:40: 
10:16:41: Using directshow input
10:16:41: Scene buffering time set to 400
10:16:41: ------------------------------------------
10:16:41: Video Encoding: x264
10:16:41:     fps: 30
10:16:41:     width: 1920, height: 1080
10:16:41:     preset: veryfast
10:16:41:     profile: high
10:16:41:     keyint: 250
10:16:41:     CBR: yes
10:16:41:     CFR: yes
10:16:41:     max bitrate: 3300
10:16:41:     buffer size: 3300
10:16:41: ------------------------------------------
10:16:41: MMDeviceAudioSource: Frequency for device 'Realtek Digital Output (Realtek High Definition Audio)' is 384000, samples per sec is 48000
10:16:41: MMDeviceAudioSource: Frequency for device 'Microphone (2- USB audio CODEC)' is 176400, samples per sec is 44100
10:17:01: ------------------------------------------
10:17:01:     device: Elgato Video Capture,
10:17:01:     device id \\?\usb#vid_0fd9&pid_0037&mi_01#7&3aadca83&0&0001#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\{9b365890-165f-11d0-a195-0020afd156e4},
10:17:01:     chosen type: UYVY, usingFourCC: false, res: 80x60 - 720x480, frameIntervals: 333667-333667
10:17:01:     use buffering: true - 0, fourCC: 'UYVY'
10:17:01: 
10:17:01:     device audio info - bits per sample: 16, channels: 2, samples per sec: 48000, block size: 4
10:17:01: Using directshow input
10:20:13: ++++++++++++++++++++++++++++++++++++++++++++++++++++++
10:20:13:   New Scene
10:20:20: ------------------------------------------
10:20:20:     device: Elgato Video Capture,
10:20:20:     device id \\?\usb#vid_0fd9&pid_0037&mi_01#7&3aadca83&0&0001#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\{9b365890-165f-11d0-a195-0020afd156e4},
10:20:20:     chosen type: UYVY, usingFourCC: false, res: 80x60 - 720x480, frameIntervals: 333667-333667
10:20:20:     use buffering: true - 0, fourCC: 'UYVY'
10:20:20: 
10:20:20:     device audio info - bits per sample: 16, channels: 2, samples per sec: 48000, block size: 4
10:20:20: Using directshow input
10:20:47: Total frames encoded: 7384, total frames duplicated: 28 (0.38%)
10:20:47: Total frames rendered: 7381, number of late frames: 2 (0.03%) (it's okay for some frames to be late)
10:20:48: 
10:20:48: Profiler time results:
10:20:48: 
10:20:48: ==============================================================
10:20:48: video thread frame - [100%] [avg time: 1.985 ms] [children: 72.1%] [unaccounted: 27.9%]
10:20:48: | scene->Preprocess - [66.2%] [avg time: 1.314 ms]
10:20:48: | GPU download and conversion - [5.89%] [avg time: 0.117 ms] [children: 5.14%] [unaccounted: 0.756%]
10:20:48: | | flush - [4.43%] [avg time: 0.088 ms]
10:20:48: | | CopyResource - [0.554%] [avg time: 0.011 ms]
10:20:48: | | conversion to 4:2:0 - [0.151%] [avg time: 0.003 ms]
10:20:48: Convert444Threads - [100%] [avg time: 1.002 ms] [children: 99.4%] [unaccounted: 0.599%]
10:20:48: | Convert444toNV12 - [99.4%] [avg time: 0.996 ms]
10:20:48: encoder thread frame - [100%] [avg time: 1.791 ms]
10:20:48: ==============================================================
10:20:48: 
10:20:48: 
10:20:48: Profiler CPU results:
10:20:48: 
10:20:48: ==============================================================
10:20:48: video thread frame - [cpu time: avg 1.232 ms, total 9094.86 ms] [avg calls per frame: 1]
10:20:48: | scene->Preprocess - [cpu time: avg 1.071 ms, total 7909.25 ms] [avg calls per frame: 1]
10:20:48: | GPU download and conversion - [cpu time: avg 0.05 ms, total 374.403 ms] [avg calls per frame: 1]
10:20:48: | | flush - [cpu time: avg 0.029 ms, total 218.401 ms] [avg calls per frame: 1]
10:20:48: | | CopyResource - [cpu time: avg 0.006 ms, total 46.8 ms] [avg calls per frame: 1]
10:20:48: | | conversion to 4:2:0 - [cpu time: avg 0.006 ms, total 46.801 ms] [avg calls per frame: 1]
10:20:48: Convert444Threads - [cpu time: avg 1.018 ms, total 15007.3 ms] [avg calls per frame: 2]
10:20:48: | Convert444toNV12 - [cpu time: avg 1.015 ms, total 14960.5 ms] [avg calls per frame: 2]
10:20:48: encoder thread frame - [cpu time: avg 1.165 ms, total 8595.66 ms] [avg calls per frame: 1]
10:20:48: ==============================================================
10:20:48: 
10:20:48: =====Stream End: 2013-11-28, 10:20:48=================================================
 

paibox

heros in an halfshel
Please try setting the webcam's color format to something other than MJPG, see if that helps.
 
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