User Manual

What pxf does

pxf makes the creation of edit proxies simple. It creates edit proxies from high resolution camera originals for Adobe Premiere Pro®, Apple Final Cut Pro®, Avid Media Composer®, and other professional video editing applications. pxf purposefully limits the options available for proxy transcodes to ensure that the proxies link properly with the high-resolution media.

How pxf makes proxies

All proxies generated by pxf maintain metadata data parity with the original. All metadata in the original file that the proxy format includes is copied from the original into the proxy.

Crucial metadata for proxy creation includes:

  • File name
  • Timecode
  • Audio track topology

By matching the file name precisely, pxf proxies can easily be replaced by the corresponding high-resolution originals through relinking. In cases where a proper proxy-original relationship is not established, a forced relink can be executed.

Proxy features

pxf Free and pxf Pro

  • Ability to import and apply a LUT (.cube file) during the encode process. pxf maintains a library of imported LUTs
  • A pxf watermark in the lower right portion of the frame to easily recognize when proxy footage is being used
  • Option for full-sized or half-sized proxies
  • Choice between h.264 (AVC) and h.265 (HEVC) codecs

pxf Pro features

  • Option to remove default watermark
  • Option for custom watermark or text overlay
  • Additional codecs: Apple ProRes 422 Proxy and Avid DNxHR LB

Using pxf proxies in professional NLEs

Using pxf Proxies in Apple Final Cut Pro®

Final Cut Pro supports externally generated proxy files through its Relink to Proxies command, making pxf a natural fit for editors who want faster or more controlled transcoding than FCP’s built-in engine provides.

Recommended workflow

  1. Transcode your camera originals in pxf, outputting H.264 or ProRes Proxy at either full or half resolution
  2. Copy the pxf-generated proxy files and your original camera media to your editing drive
  3. In FCP, import the originals using Leave Files in Place
  4. Choose File > Relink Files > Relink Proxy Files and point FCP to your pxf output folder
  5. In the View menu, switch to Proxy to confirm the relink succeeded

From this point, FCP manages the offline/online toggle transparently. Edit in proxy mode for performance, then switch to Optimized/Original in the View menu before color grading, effects work, or final export.

Format guidance for Final Cut Pro

pxf Pro outputs Apple ProRes Proxy, which is FCP’s preferred proxy format. H.264 is also accepted by FCP, but ProRes Proxy delivers better scrubbing performance and is strongly recommended for any project where timeline responsiveness matters.

Note on file naming

Final Cut Pro’s relink relies on filename matching, not timecode or clip metadata. If your originals are renamed during ingest or organization, rename the pxf outputs to match before relinking. Mismatched filenames require manual clip-by-clip relinking, which is time-consuming on large projects.

Using pxf Proxies in Adobe Premiere Pro®

Premiere Pro supports externally-generated proxy files through its Attach Proxies command, allowing pxf output to be linked directly to full-resolution clips in your project.

Recommended workflow

  1. Transcode your camera originals in pxf, outputting ProRes Proxy at your target frame size
  2. Import your full-resolution originals into Premiere’s Project panel
  3. Select the clips you want to attach proxies to, right-click, and choose Proxy > Attach Proxies
  4. In the dialog, point Premiere to your pxf output folder — Premiere uses a combination of criteria to match files, including file names, file extensions, and timecode
  5. Toggle proxy playback on or off using the Toggle Proxies button in the Program Monitor toolbar

Premiere ignores proxies at export by default, so your final output always uses the full-resolution originals.

Format guidance

pxf outputs Apple ProRes Proxy, which is well-suited for Premiere’s proxy workflow. H.264 is not recommended for proxies due to its Long GOP structure, which isn’t ideal for editing — intraframe formats like ProRes provide significantly better playback performance.

A critical note on audio channels

Frame rate, duration, and audio channel count must match between the proxy and the full-resolution clip in Adobe Premiere Pro proxy workflows. Mismatched audio channels result in warning dialogs and Premiere will not allow the attachment. If your camera records 4-channel audio (common on professional cameras even when only 2 channels are used), your proxy must also carry 4 channels. pxf preserves source audio channel layout by default for this reason.

Troubleshooting: proxies won’t attach in Premiere Pro

The most common cause is an audio channel mismatch. Professional cameras frequently record 4-channel or 8-channel audio even when only some channels carry signal — and Premiere requires the proxy to match that layout exactly.

pxf preserves the source audio channel topology in all proxy output, so a true mismatch should not occur. However, Premiere can still throw a channel mismatch error depending on how it interprets the proxy container relative to the original. Try the following in order:

Step 1 — Switch to QuickTime + ProRes 422 Proxy If you’re using an MP4 container, switch to QuickTime. The MP4/H.264 container only supports a limited set of audio channel configurations and will fail with anything outside that set. In pxf, select QuickTime with ProRes 422 Proxy encoding and re-transcode, then retry Attach Proxies.

Step 2 — Switch to MXF proxies If your originals are MXF files and the QuickTime proxy still fails to attach, the issue is likely how Premiere compares audio stream topology across container formats. MXF describes multichannel audio differently than QuickTime, and Premiere’s matching logic can reject the pairing even when channel counts are identical. In pxf, switch the output container to MXF and re-transcode. This keeps the proxy in the same container family as the original and resolves the mismatch in most remaining cases.

Camera families most likely to require this workaround include Sony (XAVC, XAVC-S, MXF-based FX and FX3/FX6/FX9 originals), Canon cinema line (XF-AVC, C70, C300, C500 series), Panasonic (Varicam, AU-EVA1), and JVC (GY-HC series). These cameras commonly record 4- or 8-channel audio with empty tracks, which is legal MXF but can confuse Premiere’s cross-container audio topology matching.

Using pxf Proxies in Avid Media Composer®

Avid’s proxy workflow is architecturally different from FCP and Premiere. Media Composer invented the offline/online editing model, but its preferred path for external proxies requires the transcoding to happen inside Avid — which means pxf fits into the workflow at the ingest stage rather than as a drop-in proxy replacement.

How Avid manages proxy media

Avid places and manages transcoded proxies within the Avid MediaFiles folder on whichever drive you specify. Proxies must be MXF files in DNxHR or DNxHD format, placed in the correct Avid MediaFiles/MXF/ folder structure on a target drive. The default and preferred MXF flavor for editing in Media Composer is OP-Atom, where video and audio streams are stored as separate MXF files.

Recommended workflow using pxf

The cleanest path for pxf-generated proxies is to use them as the edit media from the start, with AMA-linked originals available for relink at finish:

  1. AMA-link your camera originals into a bin via File > Input > Source Browser, setting Link (not Import) in the lower left corner
  2. Transcode in pxf, outputting DNxHR LB MXF OP-Atom at ¼ raster (e.g., 1920×1080 for 4K originals)
  3. Place the pxf output files into Avid MediaFiles/MXF/1/ on your target drive
  4. In Media Composer, open a bin and drag the msmMMOB.mdb file from that folder into the bin to populate it with the proxy clips
  5. Move proxy clips into a clearly labeled proxy bin, separate from your AMA-linked originals
  6. Edit with the proxy media; keep AMA bins open in the project

Relinking to originals for finishing

With the proxy bins and original AMA bins both open, right-click your locked sequence and choose Relink. Set Relink Method to Highest Quality, check Create new sequence, and confirm. A relinked sequence will appear using the original AMA-linked camera files for output.

pxf Settings

Access Settings via the gear icon in the bottom-right corner of the main window, or through pxf > Settings… (⌘,).

Manage Watermarks adds, removes, renames, or imports custom watermark images. Choose between a library watermark or a custom text overlay. Watermark support is a Pro feature.

Manage LUTs lets you browse, import, rename, or delete .cube LUT files for use in color grading workflows.

Mode switches the interface between Light, Dark, or Auto, which follows the system appearance setting in macOS System Settings.

The build number is displayed at the bottom of the Settings window.

Legal

Adobe Premiere Pro is a registered trademark of Adobe Inc. Apple, Final Cut Pro, macOS, and ProRes are trademarks of Apple Inc. Avid and Media Composer are registered trademarks of Avid Technology, Inc.

All other product names, trademarks, and registered trademarks are the property of their respective owners. pxf is not affiliated with, endorsed by, or sponsored by Adobe Inc., Apple Inc., or Avid Technology, Inc. References to these products are for informational purposes only.