Free - Windows 7/8/10/11 - DirectShow + Media Foundation

X Codec Inspector

Q: How do I fix a codec conflict detected by X Codec Inspector?

Click Detect to open the Codec Conflict Detector. Select the filter you want to demote and use Edit Merit to set its merit to DO_NOT_USE (0x00200000) or UNLIKELY (0x00400000). DirectShow will then prefer the other decoder. This is reversible and safer than unregistering the filter.

Q: Does X Codec Inspector require administrator rights?

No. Browsing, searching, exporting and taking snapshots require no admin rights. Admin rights via UAC elevation are only needed for Register DLL, Unregister DLL and Edit Merit actions which write to protected registry keys. Windows prompts for elevation automatically.

Browse every DirectShow filter and Media Foundation Transform registered on your Windows PC. View CLSIDs, DLL paths, file versions, media types, pin directions and merit values. Detect codec conflicts, register or unregister DLL files, edit filter merits, and snapshot your codec state before and after installing a codec pack. Free portable EXE - no installation required.

DirectShow filters Media Foundation MFTs Codec conflict detector Merit editor 32-bit and 64-bit Register / Unregister DLL Export to HTML, CSV, JSON Snapshot and compare

X Codec Inspector

Free Windows tool

Lists all DirectShow filters and MFTs with full metadata

Detects codec conflicts - multiple decoders for the same media type

Edit filter merit values to control DirectShow priority

Snapshot and compare codec state before and after changes

Flags missing DLL files highlighted in red

Export filter list to HTML, CSV or JSON

Portable .exe - no installer, no admin rights needed to run

Download X Codec Inspector Free - Windows 7/8/10/11 - v1.1 - portable .exe

What is a DirectShow filter?

DirectShow filters are COM components that Windows media players use to decode, split and render audio and video files. Each filter has a CLSID, a merit (priority), and a set of supported media types. X Codec Inspector lists all filters registered on your system so you can see exactly which codecs are active.

What is a Media Foundation Transform?

Media Foundation Transforms (MFTs) are the modern replacement for DirectShow filters, used by Windows 8+ media pipeline, Edge, and newer applications. MFTs handle hardware-accelerated decoding for H.264, HEVC, AV1 and other modern formats via Intel Quick Sync, NVDEC and DXVA.

What does merit control?

Merit is a priority value that DirectShow uses to decide which filter to use when multiple decoders support the same media type. Higher merit = preferred. Values: PREFERRED (0x800000), NORMAL (0x600000), UNLIKELY (0x400000), DO_NOT_USE (0x200000). X Codec Inspector lets you edit merit values to resolve codec conflicts without uninstalling filters.

Online tool below

Use the DirectShow GUID Lookup tool on this page to look up any filter CLSID or media type GUID - no download required.

Online tool - no download needed

DirectShow GUID and CLSID Lookup

Paste any DirectShow filter CLSID, media type GUID, or category GUID to instantly identify it. Includes a searchable reference of 150+ known DirectShow and Media Foundation identifiers.

Name	GUID	Type	Category	Notes

How to use X Codec Inspector

Diagnose codec problems on Windows in three steps

Download and run

Download the portable X-Codec-Inspector.exe and run it - no installation or admin rights required. The app scans your Windows registry and loads all registered DirectShow filters and Media Foundation Transforms automatically. Both 32-bit and 64-bit filters are listed.

Browse and search

Click any filter to see its CLSID, DLL path, file version, merit value, pin directions and supported media types. Use the search box to filter by name or GUID. Switch between DirectShow and Media Foundation tabs. Use Health Check to highlight filters with missing DLL files.

Fix codec conflicts

Click Detect to see all media types handled by more than one filter. Use Edit Merit to lower or raise a filter's priority without uninstalling it. Take a snapshot before installing a codec pack, install it, reload, then Compare Snapshot to see exactly which filters were added or removed.

Features

Everything X Codec Inspector can do

DirectShow

Filter inspection

All registered DirectShow filters
CLSID, DLL path, file version
Company and product name
Merit value with label
Pin directions and media types
32-bit and 64-bit filter separation

Diagnostics

Conflict detection and repair

Conflict detector - multiple decoders per type
Health check - missing DLL detection
Edit merit to fix priority conflicts
Register and unregister DLL files
Snapshot and compare codec state
Export to HTML, CSV or JSON

Media Foundation

MFT inspection

All registered MFTs via MFTEnumEx
Video and audio decoders and encoders
Hardware-accelerated MFT detection
Input and output media types
Multiplexers and demultiplexers
Video and audio effects

X Codec Inspector in action

Free DirectShow filter and MFT viewer for Windows

X Codec Inspector - free DirectShow filter viewer showing filter list, CLSID, DLL path, merit values and media types on Windows 11

FAQ

Frequently asked questions

What is a DirectShow filter and why do I need to inspect them?

A DirectShow filter is a COM component registered in the Windows registry that handles a specific part of media playback - decoding H.264, splitting MKV files, rendering audio, and so on. When media playback breaks after installing a codec pack, it is usually because two filters are competing for the same media type and the wrong one is winning. X Codec Inspector shows all registered filters, their media types and merit values, so you can identify and resolve the conflict.

How do I fix a codec conflict detected by X Codec Inspector?

Click the Detect button to open the Codec Conflict Detector. It lists every media type handled by more than one filter, ranked by severity. Select the filter you want to demote, right-click or use the Edit Merit button, and set its merit to DO_NOT_USE (0x00200000) or UNLIKELY (0x00400000). DirectShow will then prefer the other decoder. This is safer than unregistering the filter because the change can be reversed by editing the merit again.

What is the difference between DirectShow and Media Foundation?

DirectShow is the legacy Windows media pipeline, used by older players like Windows Media Player, VLC (with filters), MPC-HC, and most third-party decoders like LAV Filters. Media Foundation is the modern replacement introduced with Windows Vista and fully adopted in Windows 8+. MFTs handle hardware-accelerated decoding for H.264, HEVC and AV1 via Intel Quick Sync, NVDEC and DXVA. X Codec Inspector shows both in separate tabs.

How does the Snapshot feature work?

Click the Snapshot button to capture the current list of all DirectShow filters or MFTs. Then install or remove a codec pack, click Reload to refresh the filter list, and click Compare Snapshot. The comparison window shows exactly which filters were added (in green) and which were removed (in red). This is useful for auditing what a codec pack installer actually does to your system.

Does X Codec Inspector require administrator rights?

No. X Codec Inspector runs without admin rights for browsing, searching, exporting and taking snapshots. Admin rights via UAC elevation are only needed for the Register DLL, Unregister DLL and Edit Merit actions, because these write to protected parts of the Windows registry. Windows will automatically prompt for elevation when you use those features.

What Windows versions does X Codec Inspector support?

X Codec Inspector supports Windows 7, 8, 8.1, 10 and 11 in both 32-bit and 64-bit editions. The Media Foundation tab requires Windows 7 or later with Media Foundation installed (all editions of Windows 7+ include it except Home Premium N and Home Basic N without the Media Feature Pack).

X Codec Inspector

DirectShow GUID and CLSID Lookup

Diagnose codec problems on Windows in three steps

Download and run

Browse and search

Fix codec conflicts

Everything X Codec Inspector can do

Filter inspection

Conflict detection and repair

MFT inspection

Free DirectShow filter and MFT viewer for Windows

Frequently asked questions

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