Merge lp:~vanvugt/mir/camera-fast-mode into lp:mir

[Daniel van Vugt]

camera: Add ultrafast mode (which also lowers resolution)

With a high speed camera this provides a convenient visual test for
minimal latency. Although you should also use fullscreen at the
same time to get lowest latency (bypass): -u -f

[Mir CI Bot (mir-ci-bot)]

PASSED: Continuous integration, rev:3777
https://mir-jenkins.ubuntu.com/job/mir-ci/2021/
Executed test runs:
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-mir/2590
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-0-fetch/2653
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=vivid+overlay/2645
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=xenial+overlay/2645
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-1-sourcepkg/release=yakkety/2645
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=yakkety/2619
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=clang,platform=mesa,release=yakkety/2619/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial+overlay/2619
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=xenial+overlay/2619/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=yakkety/2619
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=amd64,compiler=gcc,platform=mesa,release=yakkety/2619/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=android,release=vivid+overlay/2619
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=cross-armhf,compiler=gcc,platform=android,release=vivid+overlay/2619/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=android,release=vivid+overlay/2619
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=android,release=vivid+overlay/2619/artifact/output/*zip*/output.zip
    SUCCESS: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=mesa,release=xenial+overlay/2619
        deb: https://mir-jenkins.ubuntu.com/job/build-2-binpkg-mir/arch=i386,compiler=gcc,platform=mesa,release=xenial+overlay/2619/artifact/output/*zip*/output.zip

Click here to trigger a rebuild:
https://mir-jenkins.ubuntu.com/job/mir-ci/2021/rebuild

review: Approve (continuous-integration)

[Alexandros Frantzis (afrantzis)]

review: Approve

[Cemil Azizoglu (cemil-azizoglu)]

ok

review: Approve

=== modified file 'examples/camera.c'
--- examples/camera.c	2016-10-05 08:42:26 +0000
+++ examples/camera.c	2016-10-20 10:19:40 +0000
@@ -373,15 +373,25 @@
     unsigned int win_height = 1;
 
     char const* dev_video = "/dev/video0";
+    mir_eglapp_bool ultrafast = 0;
     struct mir_eglapp_arg custom_args[] =
     {
         {"-d <path>", "=", &dev_video, "Path to camera device"},
+        {"-u", "!", &ultrafast, "Ultra fast mode (low resolution)"},
         {NULL, NULL, NULL, NULL},
     };
     if (!mir_eglapp_init(argc, argv, &win_width, &win_height, custom_args))
         return 1;
 
-    Camera *cam = open_camera(dev_video, camera_pref_resolution, 1);
+    // By default we prefer high resolution and low CPU usage but if you
+    // ask for ultrafast mode expect low resolution and high CPU usage...
+    enum CameraPref pref = camera_pref_resolution;
+    if (ultrafast)
+    {
+        pref = camera_pref_speed;
+        mir_surface_set_swapinterval(mir_eglapp_native_surface(), 0);
+    }
+    Camera *cam = open_camera(dev_video, pref, 1);
     if (!cam)
     {
         fprintf(stderr, "Failed to set up camera device\n");