Open stweily opened 5 months ago
I have never tested 4k camera.
The library is based on DirectShow which is legacy technology, so that could be the reason. please refer the article below. https://stackoverflow.com/questions/63393696/4k-mjpeg-camera-video-preview-with-delay-on-windows-10
The other possibility is a lack of transfer rate. I'm not familiar with transfer rate or video codec, forgive me if I tell you wrong information.
What VideoFormat are you using? I assume that you are using YUY2 format with USB2.0 interface.
3840 x 2160 image has 8294400 pixels. Single pixel is consist of RGB 24bit, so single frame is about 23MB with uncompressed.
Video is compressed with YUY2 which compression rate is 66%, single frame is about 15MB.
USB2.0 band width is 480Mbps in spec, but it actually may 240Mbps(=30MB). Frame rate 1-2fps may be reasonable.
我从未测试过 4k 相机。
该库基于 DirectShow,这是传统技术,因此这可能就是原因。 请参考下面的文章。 https://stackoverflow.com/questions/63393696/4k-mjpeg-camera-video-preview-with-delay-on-windows-10
另一种可能性是传输速率不足。 我对传输速率或视频编解码器不熟悉,如果我告诉你错误的信息,请原谅我。
您使用什么视频格式?我假设您使用的是带有USB2.0接口的YUY2格式。
3840 x 2160 图像有 8294400 像素。 单个像素由RGB 24bit组成,因此单帧未压缩时约为23MB。
视频采用YUY2压缩,压缩率为66%,单帧约15MB。
USB2.0的带宽规格上是480Mbps,但实际上可能是240Mbps(=30MB)。 帧速率 1-2fps 可能比较合理。
but use AmCap its can 4K 30fps, use WPFMediaKit.Core (also directshow ) it 4K12 FPS!
Oh, really? Could you show me a dump of return value of UsbCamera.GetVideoFormat().
var formats = UsbCamera.GetVideoFormat(cameraIndex);
// select the format you want.
foreach (var item in formats) Console.WriteLine(item);
哦真的吗? 你能给我看一下 UsbCamera.GetVideoFormat() 返回值的转储吗?
var formats = UsbCamera.GetVideoFormat(cameraIndex); // select the format you want. foreach (var item in formats) Console.WriteLine(item);
(1) which VideoFormat are you using? formats[2]? that is [Video], [MJPG], 3840,2160. (2) formats[0] works fine in 30fps?
(1) which VideoFormat are you using? formats[2]? that is [Video], [MJPG], 3840,2160. (2) formats[0] works fine in 30fps?
this is amCAP (1) I will use formats[2] and hope it work, (2) formats[0] works fine in 24- 28 fps, its ok this is our UsbCamera
Why fps = 1 or2 only at 3840 2160 resolution? if 1920 1080 its nomal at 30 fps.