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2026-09-27

设置摄像头格式 - SetCameraFormat ​

函数简介 ​

修改已打开摄像头的像素大小、帧率和 FOURCC。句柄须由 OpenCamera、OpenCameraByName 或 OpenCameraEx 得到。

多数 USB / 采集卡改分辨率会重开设备。成功后用 GetVideoWidth / GetVideoHeight 读取实际值。

本接口只作用于视频句柄，不改变 BindWindowEx display="camera" 的绑定会话。绑定会话的分辨率在绑定时由 SetConfig 的 CameraWidth / CameraHeight / CameraFps / CameraFourcc 决定。

接口名称 ​

SetCameraFormat

DLL调用 ​

c
int32_t SetCameraFormat(int64_t instance, int64_t videoHandle, int32_t width, int32_t height, double fps, const char* fourcc);

参数说明 ​

参数名类型说明
instance长整数型OLAPlug对象的指针，由 CreateCOLAPlugInterFace 接口生成。
videoHandle长整数型摄像头视频句柄。传入视频文件句柄会失败。
width整数型请求像素宽。0 表示保持当前值。
height整数型请求像素高。0 表示保持当前值。
fps双精度浮点数请求帧率。0 表示保持当前值。
fourcc文本型请求像素格式，如 "MJPG"。空字符串表示保持当前值。

示例 ​

SDK 调用 ​

cpp
#include "OLAPlugServer.h"

OLAPlugServer ola;
long handle = ola.OpenCamera(0);
int ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG");
csharp
using OLAPlug;

var ola = new OLAPlugServer();
long handle = ola.OpenCamera(0);
int ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG");
python
from OLAPlugServer import OLAPlugServer

ola = OLAPlugServer()
handle = ola.OpenCamera(0)
ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG")
java
import com.olaplug.OLAPlugServer;

OLAPlugServer ola = new OLAPlugServer();
long handle = ola.OpenCamera(0);
int ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG");
go
import "github.com/ola/olaplug/olaplug"

ola, _ := olaplug.NewOLAPlugServer("OLAPlug_x64.dll")
defer ola.ReleaseObj()
handle := ola.OpenCamera(0)
ret := ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG")
rust
use olaplug::OLAPlugServer;

let ola = OLAPlugServer::new("OLAPlug_x64.dll").unwrap();
let handle = ola.open_camera(0);
let ret = ola.set_camera_format(handle, 1280, 720, 30.0, "MJPG");
cpp
var ola = com("OlaPlug.OlaSoft")
var handle = ola.OpenCamera(0)
var ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG")
vbscript
Set ola = CreateObject("OlaPlug.OlaSoft")
handle = ola.OpenCamera(0)
ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG")
text
.局部变量 ola, OLAPlug
ola.创建 ()
handle ＝ ola.OpenCamera(0)
ret ＝ ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG")
aardio
import OLAPlugServer;
var ola = OLAPlugServer();
var handle = ola.OpenCamera(0);
var ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG");
text
变量 ola <类型 = OLAPlugServer>
ola = 新建 OLAPlugServer
长整数 handle = ola.OpenCamera(0)
整数 ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG")
cpp
#include "OLAPlugServer.h"

OLAPlugServer ola;
long handle = ola.OpenCamera(0);
int ret = ola.SetCameraFormat(handle, 1280, 720, 30.0, "MJPG");

原生 DLL 调用 ​

cpp
SetCameraFormat(instance, videoHandle, 1280, 720, 30.0, "MJPG");
csharp
using System.Runtime.InteropServices;

[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int SetCameraFormat(long ola, long videoHandle, int width, int height, double fps, string fourcc);

SetCameraFormat(instance, videoHandle, 1280, 720, 30.0, "MJPG");
python
from ctypes import CDLL, c_int, c_int64, c_double, c_char_p

ola = CDLL("OLAPlug_x64.dll")
ola.CreateCOLAPlugInterFace.restype = c_int64
ola.SetCameraFormat.restype = c_int
ola.SetCameraFormat.argtypes = [c_int64, c_int64, c_int, c_int, c_double, c_char_p]
ola.SetCameraFormat(instance, video_handle, 1280, 720, 30.0, b"MJPG")

返回值 ​

返回值说明
1成功。
0失败。句柄无效、不是摄像头，或设备拒绝该格式。

注意事项 ​

项目说明
只接受摄像头句柄视频文件句柄返回 0。
读实际值成功后宽高以首帧为准，比驱动属性更可靠。
可选规格绑定或打开前用 EnumCameras 查看驱动报告的 formats。