working v4l2 in rust, swapping bytes

Cargo.lock

@@ -469,6 +469,29 @@ dependencies = [
  "rustc-demangle",
 ]
 
+[[package]]
+name = "bindgen"
+version = "0.65.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cfdf7b466f9a4903edc73f95d6d2bcd5baf8ae620638762244d3f60143643cc5"
+dependencies = [
+ "bitflags 1.3.2",
+ "cexpr",
+ "clang-sys",
+ "lazy_static",
+ "lazycell",
+ "log",
+ "peeking_take_while",
+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "syn 2.0.48",
+ "which",
+]
+
 [[package]]
 name = "bit-set"
 version = "0.5.3"
@@ -645,6 +668,15 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6d43a04d8753f35258c91f8ec639f792891f748a1edbd759cf1dcea3382ad83c"
 
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -672,6 +704,17 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b0fc239e0f6cb375d2402d48afb92f76f5404fd1df208a41930ec81eda078bea"
 
+[[package]]
+name = "clang-sys"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "67523a3b4be3ce1989d607a828d036249522dd9c1c8de7f4dd2dae43a37369d1"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading 0.8.1",
+]
+
 [[package]]
 name = "clipboard-win"
 version = "5.1.0"
@@ -965,6 +1008,12 @@ dependencies = [
  "litrs",
 ]
 
+[[package]]
+name = "dotenv"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77c90badedccf4105eca100756a0b1289e191f6fcbdadd3cee1d2f614f97da8f"
+
 [[package]]
 name = "downcast-rs"
 version = "1.2.0"
@@ -1078,6 +1127,12 @@ dependencies = [
  "winit",
 ]
 
+[[package]]
+name = "either"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11157ac094ffbdde99aa67b23417ebdd801842852b500e395a45a9c0aac03e4a"
+
 [[package]]
 name = "emath"
 version = "0.26.2"
@@ -1467,6 +1522,12 @@ dependencies = [
  "xml-rs",
 ]
 
+[[package]]
+name = "glob"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2fabcfbdc87f4758337ca535fb41a6d701b65693ce38287d856d1674551ec9b"
+
 [[package]]
 name = "glow"
 version = "0.13.1"
@@ -1800,6 +1861,12 @@ version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
+[[package]]
+name = "lazycell"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
+
 [[package]]
 name = "libc"
 version = "0.2.153"
@@ -2283,6 +2350,12 @@ dependencies = [
  "rusticata-macros",
 ]
 
+[[package]]
+name = "peeking_take_while"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "19b17cddbe7ec3f8bc800887bab5e717348c95ea2ca0b1bf0837fb964dc67099"
+
 [[package]]
 name = "percent-encoding"
 version = "2.3.1"
@@ -2379,6 +2452,16 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e8cf8e6a8aa66ce33f63993ffc4ea4271eb5b0530a9002db8455ea6050c77bfa"
 
+[[package]]
+name = "prettyplease"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a41cf62165e97c7f814d2221421dbb9afcbcdb0a88068e5ea206e19951c2cbb5"
+dependencies = [
+ "proc-macro2",
+ "syn 2.0.48",
+]
+
 [[package]]
 name = "proc-macro-crate"
 version = "1.3.1"
@@ -2711,6 +2794,12 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "shlex"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
+
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.1"
@@ -2892,6 +2981,7 @@ dependencies = [
  "anyhow",
  "crossbeam",
  "crossbeam-channel",
+ "dotenv",
  "eframe",
  "egui",
  "indicatif",
@@ -2900,6 +2990,7 @@ dependencies = [
  "png",
  "pyo3",
  "serde",
+ "v4l",
 ]
 
 [[package]]
@@ -3136,6 +3227,26 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "v4l"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8fbfea44a46799d62c55323f3c55d06df722fbe577851d848d328a1041c3403"
+dependencies = [
+ "bitflags 1.3.2",
+ "libc",
+ "v4l2-sys-mit",
+]
+
+[[package]]
+name = "v4l2-sys-mit"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6779878362b9bacadc7893eac76abe69612e8837ef746573c4a5239daf11990b"
+dependencies = [
+ "bindgen",
+]
+
 [[package]]
 name = "version_check"
 version = "0.9.4"
@@ -3477,6 +3588,18 @@ dependencies = [
  "web-sys",
 ]
 
+[[package]]
+name = "which"
+version = "4.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87ba24419a2078cd2b0f2ede2691b6c66d8e47836da3b6db8265ebad47afbfc7"
+dependencies = [
+ "either",
+ "home",
+ "once_cell",
+ "rustix 0.38.31",
+]
+
 [[package]]
 name = "widestring"
 version = "1.0.2"

Cargo.toml

@@ -13,6 +13,7 @@ crate-type = ["rlib", "cdylib"]
 anyhow = "1.0.77"
 crossbeam = "0.8.4"
 crossbeam-channel = "0.5.11"
+dotenv = "0.15.0"
 eframe = "0.26.2"
 egui = "0.26.2"
 indicatif = "0.17.7"
@@ -21,3 +22,4 @@ pcap-parser = { version = "0.14.1", features = ["data"] }
 png = "0.17.10"
 pyo3 = { version = "0.20.0", "features" = ["extension-module"] }
 serde = { version = "1.0.193", features = ["derive", "serde_derive", "alloc"] }
+v4l = { version = "0.14.0", features = ["v4l2"], default-features = false }

examples/live.rs

@@ -1,47 +1,45 @@
-use indicatif::ProgressBar;
+use dotenv::dotenv;
-use std::fs::File;
 use std::io::Write;
-use thermaldecoder::{Frame, Header, HDR_SIZE};
+use thermaldecoder::{Header, HDR_SIZE};
-
+use v4l::video::Output;
-// fn main() -> Result<(), eframe::Error> {
-//     env_logger::init(); // Log to stderr (if you run with `RUST_LOG=debug`).
-//     let options = eframe::NativeOptions {
-//         viewport: egui::ViewportBuilder::default().with_inner_size([600.0, 800.0]),
-//         ..Default::default()
-//     };
-//     let (sender, receiver) = crossbeam::channel::unbounded();
-//     eframe::run_native(
-//         "Image Viewer",
-//         options,
-//         Box::new(|cc| {
-//             // This gives us image support:
-//             egui_extras::install_image_loaders(&cc.egui_ctx);
-//             Box::<MyApp>::default()
-//         }),
-//     )
-// }
-
-// #[derive(Default)]
-// struct MyApp {}
-
-// impl eframe::App for MyApp {
-//     fn update(&mut self, ctx: &egui::Context, _frame: &mut eframe::Frame) {
-//         egui::CentralPanel::default().show(ctx, |ui| {
-//             egui::ScrollArea::both().show(ui, |ui| {
-//                 ui.add(egui::Image::new().rounding(10.0));
-
-//                 ui.image(egui::include_image!("ferris.svg"));
-//             });
-//         });
-//     }
-// }
 
 fn main() -> anyhow::Result<()> {
-    // get the default Device
+    dotenv().ok();
-    let device = pcap::Device::lookup()
+    let device = match std::env::var("THERMALCAM_IFACE=enp1s0f0") {
+        Ok(d) => {
+            let device = pcap::Device::list()
+                .expect("device list failed")
+                .into_iter()
+                .find(|x| x.name == d)
+                .expect(&format!("could not find device {}", d));
+            device
+        }
+        Err(_) => pcap::Device::lookup()
             .expect("device lookup failed")
-        .expect("no device available");
+            .expect("no device available"),
+    };
+    // get the default Device
+
     println!("Using device {}", device.name);
+    let output = std::env::args()
+        .nth(1)
+        .expect("required output file argument");
+    println!("Using output v4l2loopback device {}", output);
+
+    const WIDTH: usize = 288;
+    const HEIGHT: usize = 384;
+    let fourcc_repr = [
+        b'Y', // | 0b10000000
+        b'1', b'6',
+        b' ', // Note: not using b' ' | 0x80, (V4L2_PIX_FMT_Y16_BE)
+              // because VID_S_FMT ioctl returns EINVAL, so just swap the bytes here
+    ];
+    let fourcc = v4l::format::FourCC { repr: fourcc_repr };
+    let mut out = v4l::Device::with_path(output)?;
+    // To find the fourcc code, use v4l2-ctl --list-formats-out /dev/video0
+    // (or read the source :)
+    let format = v4l::Format::new(WIDTH as u32, HEIGHT as u32, fourcc);
+    Output::set_format(&out, &format)?;
 
     // Setup Capture
     let mut cap = pcap::Capture::from_device(device)
@@ -51,12 +49,13 @@ fn main() -> anyhow::Result<()> {
         .unwrap();
 
     // get a packet and print its bytes
-    let mut parts = vec![];
+    const PACKET_LEN: usize = 6972;
-    let pb = ProgressBar::new(1024);
+    const FRAME_LEN: usize = WIDTH * HEIGHT * 2;
-    let mut out = File::create("output.raw")?;
+    let mut frame = [0u8; FRAME_LEN];
+    let mut len = 0;
     while let Ok(p) = cap.next_packet() {
         let data = p.data;
-        if data.len() != 6972 {
+        if data.len() != PACKET_LEN {
             continue;
         }
         let data = &data[0x2a..];
@@ -65,18 +64,24 @@ fn main() -> anyhow::Result<()> {
             Err(_) => continue,
         };
         let data = &data[HDR_SIZE..];
-        if header.part == 0 && parts.len() > 0 {
+        if (header.part == 0 && len > 0)
-            let frame = Frame {
+            // do not write out of bounds - would panic, instead just skip
-                header,
+            || (data.len() + len > FRAME_LEN)
-                raw: parts.concat(),
+        {
-            };
+            if len == FRAME_LEN {
-            if frame.raw.len() == 384 * 288 * 2 {
+                // swap the bytes, we are using LE, not BE, 16 bit grayscale
-                out.write_all(&frame.raw)?;
+                // possibly limitation of current v4l2loopback or v4l rust wrapper or libv4l2
-                pb.inc(1);
+                let mut swapped = [0u8; FRAME_LEN];
+                for i in 0..FRAME_LEN / 2 {
+                    swapped[i * 2] = frame[i * 2 + 1];
+                    swapped[i * 2 + 1] = frame[i * 2];
                 }
-            parts.clear();
+                out.write_all(&swapped[..])?;
             }
-        parts.push(data.to_vec());
+            len = 0;
+        }
+        frame[len..len + data.len()].copy_from_slice(data);
+        len += data.len();
     }
     Ok(())
 }

replay.py

@@ -4,6 +4,10 @@
  
 import base64
 from scapy.all import *
+from dotenv import load_dotenv
+import os
+
+load_dotenv()
  
 # Base64 encoded packet data 
 encoded_packet = "////////AAFsWfAKCABFAAA4KB0AAIARkEfAqAABwKgA/x+bH5wA2QAAASABgBtAACAAAAAAAAAADwAAAAEAAAEAACArAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAP//////////////////////////////////////////AAAAAAAAAAIBAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"
@@ -16,5 +20,8 @@ decoded_packet = base64.b64decode(encoded_packet)
 packet = Ether(decoded_packet)
 #print(packet.show(dump=True))
  
+iface = os.environ.get('THERMALCAM_IFACE', 'enp1s0f0')
+print(f'using interface {iface}')
+
 # (packet)
-sendp(packet, iface="enp1s0f0")
+sendp(packet, iface=iface)

run_live.sh

@@ -1,3 +1,13 @@
 #!/bin/bash
 cd $(dirname $0)
-sudo ./venv/bin/python ./decode.py --live
+
+set -e
+
+# Python works but stutters
+#sudo ./venv/bin/python ./decode.py --live
+cargo build --release --example live
+TARGET=./target/release/examples/live
+# setcap does not work yet (EPERM on socket AF_PACKET)
+# sudo setcap cap_net_raw,cap_net_admin=eip $TARGET
+#sudo strace -f -o live.strace $TARGET /dev/video0
+sudo $TARGET /dev/video0

start.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+. .env
+IFACE=$THERMALCAM_IFACE
+echo "using iface $IFACE"
+echo "checking mtu"
+mtu=$(ip link show ${IFACE} | grep -o 'mtu [0-9]*' | gawk '{print $2}')
+echo "mtu = $mtu"
+if [ $mtu -lt 9000 ]; then
+	echo "setting mtu to 9000"
+	sudo ip link set $IFACE mtu 9000
+fi
+sudo venv/bin/python ./replay.py