updated changelog and package version

com.unity.perception/CHANGELOG.md

 The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
 
-## Unreleased
+## [0.8.0-preview.4] - 2021-07-05
 
 ### Upgrade Notes
 
+
-Added random seed field to the Run in Unity Simulation Window
+Added random seed field to the Run in Unity Simulation Window.
-Increased color variety in instance segmentation images
+Increased color variety in instance segmentation images.
-Upgraded capture package dependency to 0.0.10-preview.22 to fix an issue with URP where post processing effects were not included when capturing images.
+Upgraded capture package dependency to 0.0.10-preview.23 to fix two issues: (1) Post processing effects were not included when capturing images in URP (2) RGB images were upside-down when post processing effects were enabled and FXAA disabled.
 
 ### Deprecated
 
+
-Fixed an issue where Simulation Delta Time values larger than 100 seconds (in Perception Camera) would cause incorrect capture scheduling behavior.
+Fixed an issue where Simulation Delta Time values larger than 100 seconds in Perception Camera would cause incorrect capture scheduling behavior.
-Fixed an issue where Simulation Delta Time values larger than 100 seconds (in Perception Camera) would cause incorrect capture scheduling behavior.
+
+### Upgrade Notes
+
+### Known Issues
+
+### Added
+
+
+### Deprecated
+
+### Removed
 
 ### Fixed
 

com.unity.perception/package.json

   "displayName": "Perception",
   "name": "com.unity.perception",
   "unity": "2019.4",
-  "version": "0.8.0-preview.3",
+  "version": "0.8.0-preview.4",
   "samples": [
     {
       "displayName": "Tutorial Files",