Version 6.2.0 (#733)

* Adding AV1 (NVENC) encoder for FFmpeg-based AV1 hardware encoding on NVIDIA GPUs (RTX 4000+) with quality-focused defaults including spatial/temporal AQ, lookahead, and multipass support
* Adding #724 "exit" option to the After Conversion dropdown, which closes FastFlix after all queue items complete (thanks to jrff123)
* Adding #731 OpenCL Support setting (Auto/Disable) with re-detection button in Application Locations settings (thanks to sks2012)
* Adding favicon to root of repo so it shows up on fastflix.org (thanks to Balthazar)
* Adding encoding history feature with browsable history window, "Apply Last Used Settings" menu action, and startup opt-in prompt
* Adding FFmpeg 8.0+ version check on startup with option to download latest FFmpeg on Windows
* Adding "Keep source format" option to Audio Normalize, which detects and uses the same audio codec and bitrate as the source video
* Adding Audio Encoders tab in Settings to view and select which FFmpeg audio encoders appear in audio codec dropdowns
* Adding Data tab to profile settings with passthrough all or remove all options for data and attachment streams
* Adding clear current video X button next to source path and "Clear Current Video" option in File menu
* Adding rotation and flip buttons to the visual crop window, allowing users to change rotation (0/90/180/270) and toggle horizontal/vertical flip without leaving the crop view
* Changing visual crop window to show the video frame with rotation and flip applied, matching the final output so crop edges can be set intuitively in the rotated view
* Changing Copy encoder to use modern FFmpeg display_rotation, display_hflip, and display_vflip for lossless rotation and flip metadata instead of deprecated rotate metadata tag, with support for MP4, MOV, MKV, and M4V containers
* Changing non-copy encoder rotation handling to use FFmpeg's built-in auto-rotation instead of manual display_rotation overrides, which also properly handles source flips from the display matrix
* Changing -fps_mode to be used instead of deprecated -vsync for frame rate control
* Fixing #725 encoder detection to check `ffmpeg -encoders` output in addition to compilation flags, so encoders like VAAPI are shown even when the build flag is absent (thanks to Davius and Generator)
* Fixing #728 rigaya encoders (NVEncC, QSVEncC, VCEEncC) now pass --dolby-vision-rpu-prm crop=true when Dolby Vision RPU copy is enabled and a crop is applied (thanks to izzy697)
* Fixing #730 6.1.1 arm no subtitles tab with VideoToolBox (Apple M1 and above) HEVC & H264 (thanks to enaveso)
* Fixing page_update() busy-wait that could deadlock the GUI thread when called reentrantly
* Fixing shutdown-while-encoding bug where the worker would lose the shutdown intent after the current encode finished, requiring a forceful GUI kill instead of graceful shutdown
* Fixing visual crop window showing incorrect bounds and dimensions when user rotation is applied, by showing the frame in pre-rotation space where crop actually operates
* Fixing video crop and dimension detection for rotated videos where display matrix rotation was not found when other side data (e.g., HDR mastering display) preceded it
* Fixing cover extraction to not be during video load and blocking, but a background task
* Fixing 6.1.1 > 6.2.0 mixed queue saving bug (thanks to Norbert)
* Removing -strict experimental from SVT-AV1 encoders (no longer needed with FFmpeg 8+)

Author: cdgriffith

.claude/settings.local.json

@@ -0,0 +1,119 @@
+{
+  "permissions": {
+    "allow": [
+      "WebSearch",
+      "WebFetch(domain:doc.qt.io)",
+      "WebFetch(domain:forum.qt.io)",
+      "WebFetch(domain:github.com)",
+      "Bash(uv run ruff check:*)",
+      "Bash(uv run:*)",
+      "Bash(python:*)",
+      "Bash(git log:*)",
+      "Bash(git show:*)",
+      "Bash(git status:*)",
+      "Bash(git diff:*)",
+      "Bash(git blame:*)",
+      "Bash(git ls-files:*)",
+      "Bash(git ls-tree:*)",
+      "Bash(git rev-parse:*)",
+      "Bash(git reflog:*)",
+      "Bash(git describe:*)",
+      "Bash(git shortlog:*)",
+      "Bash(git stash list:*)",
+      "Bash(git cat-file:*)",
+      "Bash(git remote -v:*)",
+      "Bash(git config --get:*)",
+      "Bash(git config --list:*)",
+      "Bash(gh pr list:*)",
+      "Bash(gh pr view:*)",
+      "Bash(gh pr status:*)",
+      "Bash(gh pr checks:*)",
+      "Bash(gh pr diff:*)",
+      "Bash(gh issue list:*)",
+      "Bash(gh issue view:*)",
+      "Bash(gh issue status:*)",
+      "Bash(gh repo view:*)",
+      "Bash(gh repo list:*)",
+      "Bash(gh release list:*)",
+      "Bash(gh release view:*)",
+      "Bash(gh run list:*)",
+      "Bash(gh run view:*)",
+      "Bash(gh workflow list:*)",
+      "Bash(gh workflow view:*)",
+      "Bash(gh search:*)",
+      "Bash(gh status:*)",
+      "Bash(gh auth status:*)",
+      "Bash(gh label list:*)",
+      "Bash(gh gist list:*)",
+      "Bash(gh gist view:*)",
+      "Bash(gh cache list:*)",
+      "Bash(gh ruleset list:*)",
+      "Bash(gh ruleset view:*)",
+      "Bash(gh variable list:*)",
+      "Bash(gh secret list:*)",
+      "Bash(gh project list:*)",
+      "Bash(gh project view:*)",
+      "Bash(dir:*)",
+      "Bash(find:*)",
+      "Bash(findstr:*)",
+      "Bash(type:*)",
+      "Bash(where:*)",
+      "Bash(tree:*)",
+      "Bash(whoami:*)",
+      "Bash(hostname:*)",
+      "Bash(ver:*)",
+      "Bash(fc:*)",
+      "Bash(echo:*)",
+      "Bash(Get-Content:*)",
+      "Bash(Get-ChildItem:*)",
+      "Bash(Get-Item:*)",
+      "Bash(Get-ItemProperty:*)",
+      "Bash(Get-Location:*)",
+      "Bash(Get-Process:*)",
+      "Bash(Get-Command:*)",
+      "Bash(Get-Help:*)",
+      "Bash(Get-Date:*)",
+      "Bash(Get-Host:*)",
+      "Bash(Get-Module:*)",
+      "Bash(Get-Variable:*)",
+      "Bash(Get-Alias:*)",
+      "Bash(Get-Service:*)",
+      "Bash(Select-String:*)",
+      "Bash(Select-Object:*)",
+      "Bash(Where-Object:*)",
+      "Bash(Sort-Object:*)",
+      "Bash(Format-Table:*)",
+      "Bash(Format-List:*)",
+      "Bash(Measure-Object:*)",
+      "Bash(Compare-Object:*)",
+      "Bash(Test-Path:*)",
+      "Bash(Resolve-Path:*)",
+      "Bash(Split-Path:*)",
+      "Bash(Join-Path:*)",
+      "Bash(ls:*)",
+      "Bash(xargs:*)",
+      "WebFetch(domain:ffmpeg.org)",
+      "Bash(ffmpeg -h:*)",
+      "Bash(ffmpeg:*)",
+      "WebFetch(domain:gitlab.com)",
+      "WebFetch(domain:wiki.x266.mov)",
+      "WebFetch(domain:raw.githubusercontent.com)",
+      "Bash(grep:*)",
+      "WebFetch(domain:docs.rs)",
+      "WebFetch(domain:gist.github.com)",
+      "WebFetch(domain:manpages.debian.org)",
+      "WebFetch(domain:api.github.com)",
+      "WebFetch(domain:codecalamity.com)",
+      "WebFetch(domain:www.mail-archive.com)",
+      "WebFetch(domain:trac.ffmpeg.org)",
+      "WebFetch(domain:dev.to)",
+      "WebFetch(domain:www.ffmpeg.org)",
+      "WebFetch(domain:www.phoronix.com)",
+      "Bash(copy:*)",
+      "Bash(ffprobe:*)",
+      "Bash(gh api:*)",
+      "Bash(git:*)",
+      "WebFetch(domain:docs.nvidia.com)"
+    ]
+  }
+}

.claude/skills/changelog.md

@@ -0,0 +1,57 @@
+---
+name: changelog
+description: Update the CHANGES changelog file with new entries. MUST be consulted whenever adding, modifying, or removing entries in the CHANGES file, including when referencing GitHub issues.
+user_invocable: true
+trigger: Always read this skill BEFORE writing any changelog entry. Triggered by any task that involves updating the CHANGES file, adding a fix/feature note, or referencing a GitHub issue in the changelog.
+---
+
+# Changelog Skill
+
+When updating the `CHANGES` file, follow these rules:
+
+## Entry Format
+
+Each entry is a single bullet point starting with `* `:
+
+```
+* {Verb} {description}
+```
+
+## Verbs and Ordering
+
+Entries MUST use one of these four starting verbs, and MUST appear in this order within each version section:
+
+1. **Adding** — new features
+2. **Changing** — modifications to existing behavior
+3. **Fixing** — bug fixes
+4. **Removing** — removed features or deprecated items
+
+## GitHub Issue Entries
+
+- Entries that reference a GitHub issue include the issue number after the verb: `* Fixing #725 description...`
+- Within each verb group, entries WITH issue numbers come FIRST, sorted by issue number ascending (smallest to largest)
+- Entries WITHOUT issue numbers follow after
+
+## Thanks Attribution
+
+- When an entry references a GitHub issue, thank the issue author by their **GitHub display name** (not username)
+- Look up the display name via `gh api users/{username} --jq '.name // .login'`
+- Format: `(thanks to {display name})`
+- If multiple people contributed (e.g., reporter and commenter with the fix), thank all of them
+- The thanks attribution goes at the end of the entry
+
+## Example
+
+```
+## Version 6.2.0
+
+* Adding #731 OpenCL Support setting (thanks to sks2012)
+* Adding FFmpeg 8.0+ version check on startup
+* Adding "Keep source format" option to Audio Normalize
+* Changing visual crop window to show rotated frame
+* Changing -fps_mode to be used instead of deprecated -vsync
+* Fixing #725 encoder detection to use ffmpeg -encoders (thanks to Davius and Generator)
+* Fixing #730 subtitles tab missing on ARM (thanks to enaveso)
+* Fixing cover extraction blocking video load
+* Removing -strict experimental from SVT-AV1 encoders
+```

CHANGES

@@ -1,5 +1,33 @@
 # Changelog
 
+## Version 6.2.0
+
+* Adding AV1 (NVENC) encoder for FFmpeg-based AV1 hardware encoding on NVIDIA GPUs (RTX 4000+) with quality-focused defaults including spatial/temporal AQ, lookahead, and multipass support
+* Adding #724 "exit" option to the After Conversion dropdown, which closes FastFlix after all queue items complete (thanks to jrff123)
+* Adding #731 OpenCL Support setting (Auto/Disable) with re-detection button in Application Locations settings (thanks to sks2012)
+* Adding favicon to root of repo so it shows up on fastflix.org (thanks to Balthazar)
+* Adding encoding history feature with browsable history window, "Apply Last Used Settings" menu action, and startup opt-in prompt
+* Adding FFmpeg 8.0+ version check on startup with option to download latest FFmpeg on Windows
+* Adding "Keep source format" option to Audio Normalize, which detects and uses the same audio codec and bitrate as the source video
+* Adding Audio Encoders tab in Settings to view and select which FFmpeg audio encoders appear in audio codec dropdowns
+* Adding Data tab to profile settings with passthrough all or remove all options for data and attachment streams
+* Adding clear current video X button next to source path and "Clear Current Video" option in File menu
+* Adding rotation and flip buttons to the visual crop window, allowing users to change rotation (0/90/180/270) and toggle horizontal/vertical flip without leaving the crop view
+* Changing visual crop window to show the video frame with rotation and flip applied, matching the final output so crop edges can be set intuitively in the rotated view
+* Changing Copy encoder to use modern FFmpeg display_rotation, display_hflip, and display_vflip for lossless rotation and flip metadata instead of deprecated rotate metadata tag, with support for MP4, MOV, MKV, and M4V containers
+* Changing non-copy encoder rotation handling to use FFmpeg's built-in auto-rotation instead of manual display_rotation overrides, which also properly handles source flips from the display matrix
+* Changing -fps_mode to be used instead of deprecated -vsync for frame rate control
+* Fixing #725 encoder detection to check `ffmpeg -encoders` output in addition to compilation flags, so encoders like VAAPI are shown even when the build flag is absent (thanks to Davius and Generator)
+* Fixing #728 rigaya encoders (NVEncC, QSVEncC, VCEEncC) now pass --dolby-vision-rpu-prm crop=true when Dolby Vision RPU copy is enabled and a crop is applied (thanks to izzy697)
+* Fixing #730 6.1.1 arm no subtitles tab with VideoToolBox (Apple M1 and above) HEVC & H264 (thanks to enaveso)
+* Fixing page_update() busy-wait that could deadlock the GUI thread when called reentrantly
+* Fixing shutdown-while-encoding bug where the worker would lose the shutdown intent after the current encode finished, requiring a forceful GUI kill instead of graceful shutdown
+* Fixing visual crop window showing incorrect bounds and dimensions when user rotation is applied, by showing the frame in pre-rotation space where crop actually operates
+* Fixing video crop and dimension detection for rotated videos where display matrix rotation was not found when other side data (e.g., HDR mastering display) preceded it
+* Fixing cover extraction to not be during video load and blocking, but a background task
+* Fixing 6.1.1 > 6.2.0 mixed queue saving bug (thanks to Norbert)
+* Removing -strict experimental from SVT-AV1 encoders (no longer needed with FFmpeg 8+)
+
 ## Version 6.1.1
 
 * Adding "Show completion popup message" (default off) and "Show error popup message" (default on) settings, replacing the old "Disable completion and error messages" toggle (thanks to Balthazar)

CLAUDE.md

@@ -6,7 +6,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 
 FastFlix is a Python GUI application for video encoding/transcoding using PySide6 (Qt6). It wraps FFmpeg and supports 25+ encoder backends including x264, x265, AV1 variants, VP9, VVC, and hardware encoders (NVIDIA NVEncC, Intel QSVEncC, AMD VCEEncC).
 
-**Requirements:** Python 3.13+, FFmpeg 4.3+ (5.0+ recommended)
+**Requirements:** Python 3.13+, FFmpeg 8.0+
 
 ## Build & Development Commands
 

fastflix/application.py

@@ -7,7 +7,13 @@
 import reusables
 from PySide6 import QtGui, QtWidgets, QtCore
 
-from fastflix.flix import ffmpeg_audio_encoders, ffmpeg_configuration, ffprobe_configuration, ffmpeg_opencl_support
+from fastflix.flix import (
+    ffmpeg_audio_encoders,
+    ffmpeg_video_encoders,
+    ffmpeg_configuration,
+    ffprobe_configuration,
+    ffmpeg_opencl_support,
+)
 from fastflix.language import t
 from fastflix.models.config import Config, MissingFF
 from fastflix.models.fastflix import FastFlix
@@ -86,6 +92,7 @@ def init_encoders(app: FastFlixApp, **_):
     from fastflix.encoders.gif import main as gif_plugin
     from fastflix.encoders.gifski import main as gifski_plugin
     from fastflix.encoders.ffmpeg_hevc_nvenc import main as nvenc_plugin
+    from fastflix.encoders.ffmpeg_av1_nvenc import main as ffmpeg_av1_nvenc_plugin
     from fastflix.encoders.hevc_x265 import main as hevc_plugin
     from fastflix.encoders.rav1e import main as rav1e_plugin
     from fastflix.encoders.svt_av1 import main as svt_av1_plugin
@@ -115,6 +122,7 @@ def init_encoders(app: FastFlixApp, **_):
         nvenc_plugin,
         hevc_videotoolbox_plugin,
         h264_videotoolbox_plugin,
+        ffmpeg_av1_nvenc_plugin,
         av1_plugin,
         rav1e_plugin,
         svt_av1_plugin,
@@ -171,10 +179,23 @@ def init_encoders(app: FastFlixApp, **_):
             # if "H.264/AVC" in app.fastflix.config.vceencc_encoders:
             encoders.insert(encoders.index(avc_plugin), vceencc_avc_plugin)
 
+    # Mapping from requires values to search terms for ffmpeg -encoders output.
+    # Most requires values (e.g. "vaapi", "libx264") appear directly in encoder names,
+    # but some compilation flags don't match encoder names and need explicit mapping.
+    requires_to_encoder = {
+        "cuda-llvm": "nvenc",
+    }
+
+    def _encoder_available(requires: str) -> bool:
+        if requires in app.fastflix.ffmpeg_config:
+            return True
+        search_term = requires_to_encoder.get(requires, requires)
+        return any(search_term in enc for enc in (app.fastflix.video_encoders or []))
+
     app.fastflix.encoders = {
         encoder.name: encoder
         for encoder in encoders
-        if (not getattr(encoder, "requires", None)) or encoder.requires in app.fastflix.ffmpeg_config or DEVMODE
+        if (not getattr(encoder, "requires", None)) or _encoder_available(encoder.requires) or DEVMODE
     }
 
 
@@ -183,6 +204,58 @@ def init_fastflix_directories(app: FastFlixApp):
     app.fastflix.log_path.mkdir(parents=True, exist_ok=True)
 
 
+def _handle_ffmpeg_version_warning_windows(app: FastFlixApp, container: Container):
+    msg = QtWidgets.QMessageBox(container)
+    msg.setIcon(QtWidgets.QMessageBox.Warning)
+    msg.setWindowTitle(t("FFmpeg Version Warning"))
+    msg.setText(
+        t(
+            "Your FFmpeg (libavcodec {version}) is older than the required FFmpeg 8.0+ (libavcodec 62+)."
+            " Some features may not work correctly."
+        ).format(version=app.fastflix.libavcodec_version)
+    )
+    cb = QtWidgets.QCheckBox(t("Don't show this warning again"))
+    msg.setCheckBox(cb)
+    download_btn = msg.addButton(t("Download Latest"), QtWidgets.QMessageBox.AcceptRole)
+    msg.addButton(t("Ignore"), QtWidgets.QMessageBox.RejectRole)
+    msg.exec()
+
+    if msg.clickedButton() == download_btn:
+        try:
+            container.status_bar.run_tasks(
+                [Task(t("Downloading FFmpeg"), grab_stable_ffmpeg)],
+                signal_task=True,
+                can_cancel=True,
+            )
+            ffmpeg_configuration(app)
+        except Exception:
+            logger.exception("Failed to download FFmpeg")
+
+    if cb.isChecked():
+        app.fastflix.config.suppress_ffmpeg_version_warning = True
+        app.fastflix.config.save()
+
+
+def _handle_ffmpeg_version_warning_other(app: FastFlixApp):
+    msg = QtWidgets.QMessageBox()
+    msg.setIcon(QtWidgets.QMessageBox.Warning)
+    msg.setWindowTitle(t("FFmpeg Version Warning"))
+    msg.setText(
+        t(
+            "Your FFmpeg (libavcodec {version}) is older than the required FFmpeg 8.0+ (libavcodec 62+)."
+            " Please update FFmpeg. Visit https://ffmpeg.org/download.html"
+        ).format(version=app.fastflix.libavcodec_version)
+    )
+    cb = QtWidgets.QCheckBox(t("Don't show this warning again"))
+    msg.setCheckBox(cb)
+    msg.addButton(t("OK"), QtWidgets.QMessageBox.AcceptRole)
+    msg.exec()
+
+    if cb.isChecked():
+        app.fastflix.config.suppress_ffmpeg_version_warning = True
+        app.fastflix.config.save()
+
+
 def app_setup(
     enable_scaling: bool = True,
     portable_mode: bool = False,
@@ -347,13 +420,30 @@ def app_setup(
                 except Exception:
                     logger.exception("Failed to download HDR10+ tool")
 
+    if app.fastflix.config.enable_history is None:
+        history_choice = yes_no_message(
+            t("Would you like to enable encoding history?")
+            + "\n\n"
+            + t(
+                "This keeps a local record of your completed encodings, letting you review the settings used for any past video and quickly re-apply them to new ones."
+            )
+            + "\n\n"
+            + t("All data is stored locally on your computer. Nothing is sent to the internet."),
+            title=t("Enable Encoding History"),
+        )
+        if history_choice is not None:
+            app.fastflix.config.enable_history = history_choice
+            if history_choice:
+                container.rebuild_menu()
+
     app.fastflix.config.save()
 
     # Run startup tasks (FFmpeg config, encoder init) through status bar
     startup_tasks = [
         Task(t("Gather FFmpeg version"), ffmpeg_configuration),
         Task(t("Gather FFprobe version"), ffprobe_configuration),
         Task(t("Gather FFmpeg audio encoders"), ffmpeg_audio_encoders),
+        Task(t("Gather FFmpeg video encoders"), ffmpeg_video_encoders),
         Task(t("Determine OpenCL Support"), ffmpeg_opencl_support),
         Task(t("Initialize Encoders"), init_encoders),
     ]
@@ -366,6 +456,13 @@ def app_setup(
         container.setEnabled(True)
         return app
 
+    # Check FFmpeg version (libavcodec 62 = FFmpeg 8.x)
+    if not app.fastflix.config.suppress_ffmpeg_version_warning and 0 < app.fastflix.libavcodec_version < 62:
+        if reusables.win_based:
+            _handle_ffmpeg_version_warning_windows(app, container)
+        else:
+            _handle_ffmpeg_version_warning_other(app)
+
     # Encoders are now populated — initialize the encoder UI
     container.main.init_encoders_ui()
 

fastflix/command_runner.py

@@ -133,9 +133,9 @@ def change_priority(
     def _safe_log_put(self, msg):
         """Put message to log queue with timeout to prevent blocking if GUI is dead."""
         try:
-            self.log_queue.put(msg, timeout=1.0)
+            self.log_queue.put(msg, timeout=0.1)
         except Full:
-            pass  # GUI likely dead, ignore
+            pass  # GUI likely dead or log queue full, skip
 
     def read_output(self):
         with (