feat: add GPU fallback compression and upload controls

README.md

@@ -1,8 +1,13 @@
 # AutoCompress (Vencord Plugin)
-- AutoCompress is a Vencord plugin that automatically compresses videos and other applicable media upon attempted send that exceed a configurable size limit, reducing them to a specified target size
+- AutoCompress is a Vencord plugin that automatically compresses videos, audio, images, and other applicable media upon attempted send that exceed a configurable size limit, reducing them to a specified target size
 
 ## Features
-- customizable compression settings, target file size, compression thresholds, etc.
+- customizable compression settings, target file size, compression thresholds, attachment type modes, and fallback behavior
+- bounded concurrent compression jobs so multi-file uploads do not launch every ffmpeg encode at once
+- progress overlay with ETA, upload cancellation, and a post-compression size preview
+- optional custom image/video dimensions, plus quick preset limits
+- optional prompt before compressing inserted media
+- diagnostics button in settings for ffmpeg/GPU encoder troubleshooting
 
 ## How It Works
 - works via reencoding media with ffmpeg 
@@ -17,6 +22,15 @@
 ## Notes
 - requires [ffmpeg](https://github.com/FFmpeg/FFmpeg) (and ffprobe), plugin should automatically resolve binaries - if not, set a path in the plugin settings
 - set a limit a bit below your ideal size
+- target size and compression threshold can use KB, MB, or GB units
+- use Compression Mode to limit compression to videos/audio, images, both, or neither
+- enable "Prompt to compress after every media insertion" to choose between compression and uploading originals each time AutoCompress intercepts media
+- failed files are skipped by default, but can optionally upload originals; compression results that are larger than the source can also optionally fall back to the original
+- increasing Concurrent Jobs can improve GPU video engine usage on systems that can handle multiple simultaneous encodes
 - ensure you set a realistic time limit 
 - lower resolution scaling can help encoding speed & artifacting 
-- ffmpeg will likely utilize the majority of your cpu when compressing as this plugin currently only does software encoding, support for hardware accel may happen eventually (but probably not)
+- GPU encoders are preferred when available (`h264_nvenc`, `h264_amf`, `h264_qsv`, or `h264_videotoolbox`), with software `libx264` as the final fallback
+- video-like media, including MOV and GIF files, is reencoded to MP4; audio-only media is reencoded to M4A
+- large outputs are retried at lower bitrates to get closer to the configured target
+- very large source videos may be retried at 1080p on GPU if the hardware encoder rejects the original resolution
+- large JPEG, PNG, and WebP images are compressed in-browser and are only intercepted when they exceed the configured threshold