obs-ffmpeg: Add tooltips for new NVENC settings

plugins/obs-ffmpeg/data/locale/en-US.ini

@@ -19,7 +19,9 @@ NVENC.Preset.ll="Low-Latency"
 NVENC.Preset.llhq="Low-Latency Quality"
 NVENC.Preset.llhp="Low-Latency Performance"
 NVENC.LookAhead="Look-ahead"
+NVENC.LookAhead.ToolTip="Enables dynamic B-frames. If disabled, the encoder will always use the number of B-frames specified in the 'Max B-frames' setting. If enabled, it will increase visual quality by only using however many B-frames are necessary, up to the maximum, at the cost of increased GPU utilization."
 NVENC.PsychoVisualTuning="Psycho Visual Tuning"
+NVENC.PsychoVisualTuning.ToolTip="Enables encoder settings that optimize the use of bitrate for increased perceived visual quality, especially in situations with high motion, at the cost of increased GPU utilization."
 NVENC.CQLevel="CQ Level"
 
 FFmpegSource="Media Source"
@@ -52,4 +54,4 @@ ReplayBuffer.Save="Save Replay"
 
 HelperProcessFailed="Unable to start the recording helper process. Check that OBS files have not been blocked or removed by any 3rd party antivirus / security software."
 UnableToWritePath="Unable to write to %1. Make sure you're using a recording path which your user account is allowed to write to and that there is sufficient disk space."
-WarnWindowsDefender="If Windows 10 Ransomware Protection is enabled it can also cause this error. Add OBS to the controlled folder access list in Windows Security / Virus & threat protection settings."
+WarnWindowsDefender="If Windows 10 Ransomware Protection is enabled it can also cause this error. Add OBS to the controlled folder access list in Windows Security / Virus & threat protection settings."

plugins/obs-ffmpeg/obs-ffmpeg-nvenc.c

@@ -489,10 +489,16 @@ obs_properties_t *nvenc_properties(void *unused)
 	add_profile("baseline");
 #undef add_profile
 
-	obs_properties_add_bool(props, "lookahead",
+	p = obs_properties_add_bool(props, "lookahead",
 			obs_module_text("NVENC.LookAhead"));
-	obs_properties_add_bool(props, "psycho_aq",
+	obs_property_set_long_description(p,
+			obs_module_text("NVENC.LookAhead.ToolTip"));
+
+	p = obs_properties_add_bool(props, "psycho_aq",
 			obs_module_text("NVENC.PsychoVisualTuning"));
+	obs_property_set_long_description(p,
+			obs_module_text("NVENC.PsychoVisualTuning.ToolTip"));
+
 	obs_properties_add_int(props, "gpu", obs_module_text("GPU"), 0, 8, 1);
 
 	obs_properties_add_int(props, "bf", obs_module_text("BFrames"),