diff options
| -rw-r--r-- | TODO | 4 | ||||
| -rwxr-xr-x | debug-install.sh | 2 | ||||
| -rwxr-xr-x | install.sh | 2 | ||||
| -rw-r--r-- | src/capture/nvfbc.c | 256 | ||||
| -rw-r--r-- | src/main.cpp | 2 |
5 files changed, 152 insertions, 114 deletions
@@ -34,8 +34,6 @@ NVreg_RegistryDwords. Restore nvfbc screen recording on monitor reconfiguration. Window capture doesn't work properly in _control_ game after going from pause menu to in-game (and back to pause menu). There might be some x11 event we need to catch. Same for vr-video-player. -Properly handle monitor reconfiguration (kms vaapi, nvfbc). - Monitor capture on steam deck is slightly below the game fps, but only when capturing on the steam deck screen. If capturing on another monitor, there is no issue. Is this related to the dma buf rotation issue? different modifier being slow? does this always happen? @@ -80,8 +78,6 @@ Preset is set to p5 for now but it should ideally be p6 or p7. For low latency, see https://developer.download.nvidia.com/compute/nvenc/v4.0/NVENC_VideoEncoder_API_ProgGuide.pdf (section 7.1). Remove follow focused option. -Overclocking (-oc) can overclock too much on some systems. Maybe remove the option? - Exit if X11/Wayland killed (if drm plane dead or something?) Use SRC_W and SRC_H for screen plane instead of crtc_w and crtc_h. diff --git a/debug-install.sh b/debug-install.sh index d17575c..096eefa 100755 --- a/debug-install.sh +++ b/debug-install.sh @@ -14,7 +14,7 @@ if [ -d "/usr/lib/systemd/user" ]; then fi # Not necessary, but removes the password prompt when trying to record a monitor on amd/intel or nvidia wayland setcap cap_sys_admin+ep /usr/bin/gsr-kms-server -# Not necessary, but allows use of EGL_CONTEXT_PRIORITY_LEVEL_IMG which allows gpu screen recorder to run without being limited to game fps under heavy load +# Not necessary, but allows use of EGL_CONTEXT_PRIORITY_LEVEL_IMG which allows gpu screen recorder to run without being limited to game fps under heavy load on AMD/Intel setcap cap_sys_nice+ep /usr/bin/gpu-screen-recorder echo "Successfully installed gpu-screen-recorder (debug)" @@ -16,7 +16,7 @@ if [ -d "/usr/lib/systemd/user" ]; then fi # Not necessary, but removes the password prompt when trying to record a monitor on amd/intel or nvidia wayland setcap cap_sys_admin+ep /usr/bin/gsr-kms-server -# Not necessary, but allows use of EGL_CONTEXT_PRIORITY_LEVEL_IMG which allows gpu screen recorder to run without being limited to game fps under heavy load +# Not necessary, but allows use of EGL_CONTEXT_PRIORITY_LEVEL_IMG which allows gpu screen recorder to run without being limited to game fps under heavy load on AMD/Intel setcap cap_sys_nice+ep /usr/bin/gpu-screen-recorder echo "Successfully installed gpu-screen-recorder" diff --git a/src/capture/nvfbc.c b/src/capture/nvfbc.c index 5acf083..9eabb18 100644 --- a/src/capture/nvfbc.c +++ b/src/capture/nvfbc.c @@ -2,6 +2,7 @@ #include "../../external/NvFBC.h" #include "../../include/cuda.h" #include "../../include/egl.h" +#include "../../include/utils.h" #include <dlfcn.h> #include <stdlib.h> #include <string.h> @@ -30,6 +31,16 @@ typedef struct { CUarray mapped_arrays[2]; CUstream cuda_stream; // TODO: asdasdsa NVFBC_TOGL_SETUP_PARAMS setup_params; + + bool direct_capture; + bool supports_direct_cursor; + bool capture_region; + uint32_t x, y, width, height; + NVFBC_TRACKING_TYPE tracking_type; + uint32_t output_id; + uint32_t tracking_width, tracking_height; + bool nvfbc_needs_recreate; + double nvfbc_dead_start; } gsr_capture_nvfbc; #if defined(_WIN64) || defined(__LP64__) @@ -157,57 +168,34 @@ static void set_vertical_sync_enabled(gsr_egl *egl, int enabled) { fprintf(stderr, "gsr warning: setting vertical sync failed\n"); } -static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec_context, AVFrame *frame) { - gsr_capture_nvfbc *cap_nvfbc = cap->priv; - - cap_nvfbc->base.video_codec_context = video_codec_context; - cap_nvfbc->base.egl = cap_nvfbc->params.egl; - - if(!gsr_cuda_load(&cap_nvfbc->cuda, cap_nvfbc->params.egl->x11.dpy, cap_nvfbc->params.overclock)) - return -1; - - if(!gsr_capture_nvfbc_load_library(cap)) { - gsr_cuda_unload(&cap_nvfbc->cuda); - return -1; +static void gsr_capture_nvfbc_destroy_session(gsr_capture_nvfbc *cap_nvfbc) { + if(cap_nvfbc->fbc_handle_created && cap_nvfbc->capture_session_created) { + NVFBC_DESTROY_CAPTURE_SESSION_PARAMS destroy_capture_params; + memset(&destroy_capture_params, 0, sizeof(destroy_capture_params)); + destroy_capture_params.dwVersion = NVFBC_DESTROY_CAPTURE_SESSION_PARAMS_VER; + cap_nvfbc->nv_fbc_function_list.nvFBCDestroyCaptureSession(cap_nvfbc->nv_fbc_handle, &destroy_capture_params); + cap_nvfbc->capture_session_created = false; } +} - const uint32_t x = max_int(cap_nvfbc->params.pos.x, 0); - const uint32_t y = max_int(cap_nvfbc->params.pos.y, 0); - const uint32_t width = max_int(cap_nvfbc->params.size.x, 0); - const uint32_t height = max_int(cap_nvfbc->params.size.y, 0); - - const bool capture_region = (x > 0 || y > 0 || width > 0 || height > 0); - - bool supports_direct_cursor = false; - bool direct_capture = cap_nvfbc->params.direct_capture; - int driver_major_version = 0; - int driver_minor_version = 0; - if(direct_capture && get_driver_version(&driver_major_version, &driver_minor_version)) { - fprintf(stderr, "Info: detected nvidia version: %d.%d\n", driver_major_version, driver_minor_version); - - // TODO: - if(version_at_least(driver_major_version, driver_minor_version, 515, 57) && version_less_than(driver_major_version, driver_minor_version, 520, 56)) { - direct_capture = false; - fprintf(stderr, "Warning: \"screen-direct\" has temporary been disabled as it causes stuttering with driver versions >= 515.57 and < 520.56. Please update your driver if possible. Capturing \"screen\" instead.\n"); - } - - // TODO: - // Cursor capture disabled because moving the cursor doesn't update capture rate to monitor hz and instead captures at 10-30 hz - /* - if(direct_capture) { - if(version_at_least(driver_major_version, driver_minor_version, 515, 57)) - supports_direct_cursor = true; - else - fprintf(stderr, "Info: capturing \"screen-direct\" but driver version appears to be less than 515.57. Disabling capture of cursor. Please update your driver if you want to capture your cursor or record \"screen\" instead.\n"); - } - */ +static void gsr_capture_nvfbc_destroy_handle(gsr_capture_nvfbc *cap_nvfbc) { + if(cap_nvfbc->fbc_handle_created) { + NVFBC_DESTROY_HANDLE_PARAMS destroy_params; + memset(&destroy_params, 0, sizeof(destroy_params)); + destroy_params.dwVersion = NVFBC_DESTROY_HANDLE_PARAMS_VER; + cap_nvfbc->nv_fbc_function_list.nvFBCDestroyHandle(cap_nvfbc->nv_fbc_handle, &destroy_params); + cap_nvfbc->fbc_handle_created = false; + cap_nvfbc->nv_fbc_handle = 0; } +} +static void gsr_capture_nvfbc_destroy_session_and_handle(gsr_capture_nvfbc *cap_nvfbc) { + gsr_capture_nvfbc_destroy_session(cap_nvfbc); + gsr_capture_nvfbc_destroy_handle(cap_nvfbc); +} + +static int gsr_capture_nvfbc_setup_handle(gsr_capture_nvfbc *cap_nvfbc) { NVFBCSTATUS status; - NVFBC_TRACKING_TYPE tracking_type; - uint32_t output_id = 0; - cap_nvfbc->fbc_handle_created = false; - cap_nvfbc->capture_session_created = false; NVFBC_CREATE_HANDLE_PARAMS create_params; memset(&create_params, 0, sizeof(create_params)); @@ -246,10 +234,10 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec goto error_cleanup; } - uint32_t tracking_width = XWidthOfScreen(DefaultScreenOfDisplay(cap_nvfbc->params.egl->x11.dpy)); - uint32_t tracking_height = XHeightOfScreen(DefaultScreenOfDisplay(cap_nvfbc->params.egl->x11.dpy)); - tracking_type = strcmp(cap_nvfbc->params.display_to_capture, "screen") == 0 ? NVFBC_TRACKING_SCREEN : NVFBC_TRACKING_OUTPUT; - if(tracking_type == NVFBC_TRACKING_OUTPUT) { + cap_nvfbc->tracking_width = XWidthOfScreen(DefaultScreenOfDisplay(cap_nvfbc->params.egl->x11.dpy)); + cap_nvfbc->tracking_height = XHeightOfScreen(DefaultScreenOfDisplay(cap_nvfbc->params.egl->x11.dpy)); + cap_nvfbc->tracking_type = strcmp(cap_nvfbc->params.display_to_capture, "screen") == 0 ? NVFBC_TRACKING_SCREEN : NVFBC_TRACKING_OUTPUT; + if(cap_nvfbc->tracking_type == NVFBC_TRACKING_OUTPUT) { if(!status_params.bXRandRAvailable) { fprintf(stderr, "gsr error: gsr_capture_nvfbc_start failed: the xrandr extension is not available\n"); goto error_cleanup; @@ -260,34 +248,42 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec goto error_cleanup; } - output_id = get_output_id_from_display_name(status_params.outputs, status_params.dwOutputNum, cap_nvfbc->params.display_to_capture, &tracking_width, &tracking_height); - if(output_id == 0) { + cap_nvfbc->output_id = get_output_id_from_display_name(status_params.outputs, status_params.dwOutputNum, cap_nvfbc->params.display_to_capture, &cap_nvfbc->tracking_width, &cap_nvfbc->tracking_height); + if(cap_nvfbc->output_id == 0) { fprintf(stderr, "gsr error: gsr_capture_nvfbc_start failed: display '%s' not found\n", cap_nvfbc->params.display_to_capture); goto error_cleanup; } } + return 0; + + error_cleanup: + gsr_capture_nvfbc_destroy_session_and_handle(cap_nvfbc); + return -1; +} + +static int gsr_capture_nvfbc_setup_session(gsr_capture_nvfbc *cap_nvfbc) { NVFBC_CREATE_CAPTURE_SESSION_PARAMS create_capture_params; memset(&create_capture_params, 0, sizeof(create_capture_params)); create_capture_params.dwVersion = NVFBC_CREATE_CAPTURE_SESSION_PARAMS_VER; create_capture_params.eCaptureType = NVFBC_CAPTURE_TO_GL; - create_capture_params.bWithCursor = (!direct_capture || supports_direct_cursor) ? NVFBC_TRUE : NVFBC_FALSE; + create_capture_params.bWithCursor = (!cap_nvfbc->direct_capture || cap_nvfbc->supports_direct_cursor) ? NVFBC_TRUE : NVFBC_FALSE; if(!cap_nvfbc->params.record_cursor) create_capture_params.bWithCursor = false; - if(capture_region) - create_capture_params.captureBox = (NVFBC_BOX){ x, y, width, height }; - create_capture_params.eTrackingType = tracking_type; + if(cap_nvfbc->capture_region) + create_capture_params.captureBox = (NVFBC_BOX){ cap_nvfbc->x, cap_nvfbc->y, cap_nvfbc->width, cap_nvfbc->height }; + create_capture_params.eTrackingType = cap_nvfbc->tracking_type; create_capture_params.dwSamplingRateMs = (uint32_t)ceilf(1000.0f / (float)cap_nvfbc->params.fps); - create_capture_params.bAllowDirectCapture = direct_capture ? NVFBC_TRUE : NVFBC_FALSE; - create_capture_params.bPushModel = direct_capture ? NVFBC_TRUE : NVFBC_FALSE; - //create_capture_params.bDisableAutoModesetRecovery = true; // TODO: - if(tracking_type == NVFBC_TRACKING_OUTPUT) - create_capture_params.dwOutputId = output_id; + create_capture_params.bAllowDirectCapture = cap_nvfbc->direct_capture ? NVFBC_TRUE : NVFBC_FALSE; + create_capture_params.bPushModel = cap_nvfbc->direct_capture ? NVFBC_TRUE : NVFBC_FALSE; + create_capture_params.bDisableAutoModesetRecovery = true; + if(cap_nvfbc->tracking_type == NVFBC_TRACKING_OUTPUT) + create_capture_params.dwOutputId = cap_nvfbc->output_id; - status = cap_nvfbc->nv_fbc_function_list.nvFBCCreateCaptureSession(cap_nvfbc->nv_fbc_handle, &create_capture_params); + NVFBCSTATUS status = cap_nvfbc->nv_fbc_function_list.nvFBCCreateCaptureSession(cap_nvfbc->nv_fbc_handle, &create_capture_params); if(status != NVFBC_SUCCESS) { fprintf(stderr, "gsr error: gsr_capture_nvfbc_start failed: %s\n", cap_nvfbc->nv_fbc_function_list.nvFBCGetLastErrorStr(cap_nvfbc->nv_fbc_handle)); - goto error_cleanup; + return -1; } cap_nvfbc->capture_session_created = true; @@ -298,15 +294,73 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec status = cap_nvfbc->nv_fbc_function_list.nvFBCToGLSetUp(cap_nvfbc->nv_fbc_handle, &cap_nvfbc->setup_params); if(status != NVFBC_SUCCESS) { fprintf(stderr, "gsr error: gsr_capture_nvfbc_start failed: %s\n", cap_nvfbc->nv_fbc_function_list.nvFBCGetLastErrorStr(cap_nvfbc->nv_fbc_handle)); + gsr_capture_nvfbc_destroy_session(cap_nvfbc); + return -1; + } + + return 0; +} + +static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec_context, AVFrame *frame) { + gsr_capture_nvfbc *cap_nvfbc = cap->priv; + + cap_nvfbc->base.video_codec_context = video_codec_context; + cap_nvfbc->base.egl = cap_nvfbc->params.egl; + + if(!gsr_cuda_load(&cap_nvfbc->cuda, cap_nvfbc->params.egl->x11.dpy, cap_nvfbc->params.overclock)) + return -1; + + if(!gsr_capture_nvfbc_load_library(cap)) { + gsr_cuda_unload(&cap_nvfbc->cuda); + return -1; + } + + cap_nvfbc->x = max_int(cap_nvfbc->params.pos.x, 0); + cap_nvfbc->y = max_int(cap_nvfbc->params.pos.y, 0); + cap_nvfbc->width = max_int(cap_nvfbc->params.size.x, 0); + cap_nvfbc->height = max_int(cap_nvfbc->params.size.y, 0); + + cap_nvfbc->capture_region = (cap_nvfbc->x > 0 || cap_nvfbc->y > 0 || cap_nvfbc->width > 0 || cap_nvfbc->height > 0); + + cap_nvfbc->supports_direct_cursor = false; + bool direct_capture = cap_nvfbc->params.direct_capture; + int driver_major_version = 0; + int driver_minor_version = 0; + if(direct_capture && get_driver_version(&driver_major_version, &driver_minor_version)) { + fprintf(stderr, "Info: detected nvidia version: %d.%d\n", driver_major_version, driver_minor_version); + + // TODO: + if(version_at_least(driver_major_version, driver_minor_version, 515, 57) && version_less_than(driver_major_version, driver_minor_version, 520, 56)) { + direct_capture = false; + fprintf(stderr, "Warning: \"screen-direct\" has temporary been disabled as it causes stuttering with driver versions >= 515.57 and < 520.56. Please update your driver if possible. Capturing \"screen\" instead.\n"); + } + + // TODO: + // Cursor capture disabled because moving the cursor doesn't update capture rate to monitor hz and instead captures at 10-30 hz + /* + if(direct_capture) { + if(version_at_least(driver_major_version, driver_minor_version, 515, 57)) + supports_direct_cursor = true; + else + fprintf(stderr, "Info: capturing \"screen-direct\" but driver version appears to be less than 515.57. Disabling capture of cursor. Please update your driver if you want to capture your cursor or record \"screen\" instead.\n"); + } + */ + } + + if(gsr_capture_nvfbc_setup_handle(cap_nvfbc) != 0) { goto error_cleanup; } - if(capture_region) { - video_codec_context->width = width & ~1; - video_codec_context->height = height & ~1; + if(gsr_capture_nvfbc_setup_session(cap_nvfbc) != 0) { + goto error_cleanup; + } + + if(cap_nvfbc->capture_region) { + video_codec_context->width = cap_nvfbc->width & ~1; + video_codec_context->height = cap_nvfbc->height & ~1; } else { - video_codec_context->width = tracking_width & ~1; - video_codec_context->height = tracking_height & ~1; + video_codec_context->width = cap_nvfbc->tracking_width & ~1; + video_codec_context->height = cap_nvfbc->tracking_height & ~1; } frame->width = video_codec_context->width; @@ -331,52 +385,38 @@ static int gsr_capture_nvfbc_start(gsr_capture *cap, AVCodecContext *video_codec return 0; error_cleanup: - if(cap_nvfbc->fbc_handle_created) { - if(cap_nvfbc->capture_session_created) { - NVFBC_DESTROY_CAPTURE_SESSION_PARAMS destroy_capture_params; - memset(&destroy_capture_params, 0, sizeof(destroy_capture_params)); - destroy_capture_params.dwVersion = NVFBC_DESTROY_CAPTURE_SESSION_PARAMS_VER; - cap_nvfbc->nv_fbc_function_list.nvFBCDestroyCaptureSession(cap_nvfbc->nv_fbc_handle, &destroy_capture_params); - cap_nvfbc->capture_session_created = false; - } - - NVFBC_DESTROY_HANDLE_PARAMS destroy_params; - memset(&destroy_params, 0, sizeof(destroy_params)); - destroy_params.dwVersion = NVFBC_DESTROY_HANDLE_PARAMS_VER; - cap_nvfbc->nv_fbc_function_list.nvFBCDestroyHandle(cap_nvfbc->nv_fbc_handle, &destroy_params); - cap_nvfbc->fbc_handle_created = false; - } - + gsr_capture_nvfbc_destroy_session_and_handle(cap_nvfbc); gsr_capture_base_stop(&cap_nvfbc->base); gsr_cuda_unload(&cap_nvfbc->cuda); return -1; } -static void gsr_capture_nvfbc_destroy_session(gsr_capture *cap) { +static int gsr_capture_nvfbc_capture(gsr_capture *cap, AVFrame *frame) { gsr_capture_nvfbc *cap_nvfbc = cap->priv; - if(cap_nvfbc->fbc_handle_created) { - if(cap_nvfbc->capture_session_created) { - NVFBC_DESTROY_CAPTURE_SESSION_PARAMS destroy_capture_params; - memset(&destroy_capture_params, 0, sizeof(destroy_capture_params)); - destroy_capture_params.dwVersion = NVFBC_DESTROY_CAPTURE_SESSION_PARAMS_VER; - cap_nvfbc->nv_fbc_function_list.nvFBCDestroyCaptureSession(cap_nvfbc->nv_fbc_handle, &destroy_capture_params); - cap_nvfbc->capture_session_created = false; + const double nvfbc_recreate_retry_time_seconds = 1.0; + if(cap_nvfbc->nvfbc_needs_recreate) { + const double now = clock_get_monotonic_seconds(); + if(now - cap_nvfbc->nvfbc_dead_start >= nvfbc_recreate_retry_time_seconds) { + cap_nvfbc->nvfbc_dead_start = now; + gsr_capture_nvfbc_destroy_session_and_handle(cap_nvfbc); + + if(gsr_capture_nvfbc_setup_handle(cap_nvfbc) != 0) { + fprintf(stderr, "gsr error: gsr_capture_nvfbc_capture failed to recreate nvfbc handle, trying again in %f second(s)\n", nvfbc_recreate_retry_time_seconds); + return -1; + } + + if(gsr_capture_nvfbc_setup_session(cap_nvfbc) != 0) { + fprintf(stderr, "gsr error: gsr_capture_nvfbc_capture failed to recreate nvfbc session, trying again in %f second(s)\n", nvfbc_recreate_retry_time_seconds); + return -1; + } + + cap_nvfbc->nvfbc_needs_recreate = false; + } else { + return 0; } - - NVFBC_DESTROY_HANDLE_PARAMS destroy_params; - memset(&destroy_params, 0, sizeof(destroy_params)); - destroy_params.dwVersion = NVFBC_DESTROY_HANDLE_PARAMS_VER; - cap_nvfbc->nv_fbc_function_list.nvFBCDestroyHandle(cap_nvfbc->nv_fbc_handle, &destroy_params); - cap_nvfbc->fbc_handle_created = false; } - cap_nvfbc->nv_fbc_handle = 0; -} - -static int gsr_capture_nvfbc_capture(gsr_capture *cap, AVFrame *frame) { - gsr_capture_nvfbc *cap_nvfbc = cap->priv; - NVFBC_FRAME_GRAB_INFO frame_info; memset(&frame_info, 0, sizeof(frame_info)); @@ -389,8 +429,10 @@ static int gsr_capture_nvfbc_capture(gsr_capture *cap, AVFrame *frame) { NVFBCSTATUS status = cap_nvfbc->nv_fbc_function_list.nvFBCToGLGrabFrame(cap_nvfbc->nv_fbc_handle, &grab_params); if(status != NVFBC_SUCCESS) { - fprintf(stderr, "gsr error: gsr_capture_nvfbc_capture failed: %s\n", cap_nvfbc->nv_fbc_function_list.nvFBCGetLastErrorStr(cap_nvfbc->nv_fbc_handle)); - return -1; + fprintf(stderr, "gsr error: gsr_capture_nvfbc_capture failed: %s (%d), recreating session after %f second(s)\n", cap_nvfbc->nv_fbc_function_list.nvFBCGetLastErrorStr(cap_nvfbc->nv_fbc_handle), status, nvfbc_recreate_retry_time_seconds); + cap_nvfbc->nvfbc_needs_recreate = true; + cap_nvfbc->nvfbc_dead_start = clock_get_monotonic_seconds(); + return 0; } //cap_nvfbc->params.egl->glClearColor(0.0f, 0.0f, 0.0f, 1.0f); @@ -434,7 +476,7 @@ static int gsr_capture_nvfbc_capture(gsr_capture *cap, AVFrame *frame) { static void gsr_capture_nvfbc_destroy(gsr_capture *cap, AVCodecContext *video_codec_context) { (void)video_codec_context; gsr_capture_nvfbc *cap_nvfbc = cap->priv; - gsr_capture_nvfbc_destroy_session(cap); + gsr_capture_nvfbc_destroy_session_and_handle(cap_nvfbc); if(cap_nvfbc) { gsr_capture_base_stop(&cap_nvfbc->base); gsr_cuda_unload(&cap_nvfbc->cuda); diff --git a/src/main.cpp b/src/main.cpp index 3c6fba6..167f8a5 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -2424,7 +2424,7 @@ int main(int argc, char **argv) { if(got_audio_data) received_audio_time = this_audio_frame_time; - // Jesus is there a better way to do this? I JUST WANT TO KEEP VIDEO AND AUDIO SYNCED HOLY FUCK I WANT TO KILL MYSELF NOW. + // Fucking hell is there a better way to do this? I JUST WANT TO KEEP VIDEO AND AUDIO SYNCED HOLY FUCK I WANT TO KILL MYSELF NOW. // THIS PIECE OF SHIT WANTS EMPTY FRAMES OTHERWISE VIDEO PLAYS TOO FAST TO KEEP UP WITH AUDIO OR THE AUDIO PLAYS TOO EARLY. // BUT WE CANT USE DELAYS TO GIVE DUMMY DATA BECAUSE PULSEAUDIO MIGHT GIVE AUDIO A BIG DELAYED!!! // This garbage is needed because we want to produce constant frame rate videos instead of variable frame rate |