work on opencv

src/backends/capture/opencv_backend.rs

@@ -1,5 +1,6 @@
-use crate::{CameraFormat, CameraInfo, NokhwaError};
-use opencv::videoio::{VideoCapture, CAP_ANY, CAP_AVFOUNDATION, CAP_MSMF, CAP_V4L2};
+use crate::{CameraFormat, CameraInfo, FrameFormat, NokhwaError, Resolution};
+use opencv::{prelude::Detail_NoBundleAdjusterTrait, videoio::{CAP_ANY, CAP_AVFOUNDATION, CAP_MSMF, CAP_PROP_FOURCC, CAP_V4L2, VideoCapture, VideoCaptureProperties, VideoCaptureTrait, VideoWriter}};
+use std::{convert::TryInto, ops::Deref};
 
 /// The backend struct that interfaces with `OpenCV`. Note that an `opencv` matching the version that this was either compiled on must be present on the user's machine. (usually 4.5.2 or greater)
 /// For more information, please see [`opencv-rust`](https://github.com/twistedfall/opencv-rust) and [`OpenCV VideoCapture Docs`](https://docs.opencv.org/4.5.2/d8/dfe/classcv_1_1VideoCapture.html).
@@ -23,6 +24,20 @@ impl OpenCvCaptureDevice {
         camera_format: Option<CameraFormat>,
         api_pref: Option<u32>,
     ) -> Result<Self, NokhwaError> {
+        let api = match api_pref {
+            Some(a) => a as i32,
+            None => get_api_pref_int() as i32,
+        };
+        let mut video_capture = match location {
+            CameraIndexType::Index(idx) => match VideoCapture::new(idx as i32, api) {
+                Ok(vc) => vc,
+                Err(why) => return Err(NokhwaError::CouldntOpenDevice(why.to_string())),
+            },
+            CameraIndexType::IPCamera(ip) => match VideoCapture::from_file(ip.deref(), api) {
+                Ok(vc) => vc,
+                Err(why) => return Err(NokhwaError::CouldntOpenDevice(why.to_string())),
+            },
+        };
     }
 }
 
@@ -46,3 +61,99 @@ fn get_api_pref_int() -> u32 {
         &_ => CAP_ANY as u32,
     }
 }
+fn set_properties(
+    vc: &mut VideoCapture,
+    res: Resolution,
+    fps: u32,
+    frame_fmt: FrameFormat
+) -> Result<(), NokhwaError> {
+    set_property_fourcc(vc, frame_fmt)?;
+    set_property_res(vc, res)?;
+    set_property_fps(vc, fps)?;
+    Ok(())
+}
+
+fn set_property_res(
+    vc: &mut VideoCapture,
+    res: Resolution,
+) -> Result<(), NokhwaError> {
+    match vc.set(
+        VideoCaptureProperties::CAP_PROP_FRAME_HEIGHT as i32,
+        f64::from(res.height()),
+    ) {
+        Ok(r) => {
+            if !r {
+                return Err(NokhwaError::CouldntSetProperty { property: "Resolution Height".to_string(), value: res.height().to_string(), error: "OpenCV bool assert failure".to_string() })
+            }
+        }
+        Err(why) => {
+            return Err(NokhwaError::CouldntSetProperty { property: "Resolution Height".to_string(), value: res.height().to_string(), error: why.to_string() })
+        }
+    }
+
+    match vc.set(
+        VideoCaptureProperties::CAP_PROP_FRAME_WIDTH as i32,
+        f64::from(res.width()),
+    ) {
+        Ok(r) => {
+            if !r {
+                return Err(NokhwaError::CouldntSetProperty { property: "Resolution Width".to_string(), value: res.width().to_string(), error: "OpenCV bool assert failure".to_string() })
+            }
+        }
+        Err(why) => {
+            return Err(NokhwaError::CouldntSetProperty { property: "Resolution Width".to_string(), value: res.width().to_string(), error: why.to_string() })
+        }
+    }
+
+    Ok(())
+}
+
+fn set_property_fps(vc: &mut VideoCapture, fps: u32) -> Result<(), NokhwaError> {
+    match vc.set(VideoCaptureProperties::CAP_PROP_FPS as i32, f64::from(fps)) {
+        Ok(r) => {
+            if !r {
+                return Err(NokhwaError::CouldntSetProperty { property: "Framerate".to_string(), value: fps.to_string(), error: "OpenCV bool assert failure".to_string() })
+            }
+        }
+        Err(why) => {
+            return Err(NokhwaError::CouldntSetProperty { property: "Framerate".to_string(), value: fps.to_string(), error: why.to_string() })
+        }
+    }
+    Ok(())
+}
+
+fn set_property_fourcc(vc: &mut VideoCapture, frame_fmt: FrameFormat) -> Result<(), NokhwaError> {
+    let fourcc = match frame_fmt {
+        FrameFormat::MJPEG => {
+            f64::from(
+                match VideoWriter::fourcc('M' as i8, 'J' as i8, 'P' as i8, 'G' as i8) {
+                    Ok(fcc) => fcc,
+                    Err(why) => return Err(NokhwaError::CouldntSetProperty { property: "FourCC".to_string(), value: "MJPG".to_string(), error: why.to_string() })
+                }
+            )
+        }
+        FrameFormat::YUYV => {
+            f64::from(
+                match VideoWriter::fourcc('Y' as i8, 'U' as i8, 'Y' as i8, 'V' as i8) {
+                    Ok(fcc) => fcc,
+                    Err(why) => return Err(NokhwaError::CouldntSetProperty { property: "FourCC".to_string(), value: "YUYV".to_string(), error: why.to_string() })
+                }
+            )
+        }
+    };
+
+    match vc.set(
+        CAP_PROP_FOURCC as i32,
+        f64::from(VideoWriter::fourcc('M' as i8, 'J' as i8, 'P' as i8, 'G' as i8).unwrap()),
+    ) {
+        Ok(r) => {
+            if !r {
+                return Err(NokhwaError::CouldntSetProperty { property: "FourCC".to_string(), value: format!("FrameFormat: {}, OpenCV FourCC {}", frame_fmt, fourcc), error: "OpenCV bool assert failure".to_string() })
+            }
+        }
+        Err(why) => {
+            return Err(NokhwaError::CouldntSetProperty { property: "FourCC".to_string(), value: format!("FrameFormat: {}, OpenCV FourCC {}", frame_fmt, fourcc), error: why.to_string() })
+        }
+    }
+    Ok(())
+}

src/lib.rs

@@ -1,7 +1,5 @@
 #![deny(clippy::pedantic)]
 #![warn(clippy::all)]
-#![allow(clippy::upper_case_acronyms)]
-#![allow(clippy::must_use_candidate)]
 
 //! # nokhwa
 //! Nokhwa(녹화): Korean word meaning "to record".