YUV Viewer (formerly Elecard YUV Viewer) — Supported Formats & Settings

YUV Viewer (formerly Elecard YUV Viewer) — Supported Formats & Settings

YUV Viewer is a lightweight utility for inspecting raw and encoded video frames in YUV and related color formats. This article summarizes the file formats, pixel formats, container/codec support, and the key settings you’ll use to view, analyze, and export frames.

Supported file types and inputs

• Raw YUV files (.yuv, .y, .raw) — planar and packed layouts.
• Single-frame image files used for testing (e.g., .bmp, .png) when imported for reference/overlay.
• Captures from video codecs where raw YUV can be extracted or piped into the tool (e.g., frames dumped from FFmpeg).

Pixel formats and color layouts

YUV Viewer supports a wide set of YUV pixel formats common in video development and testing. Expect support for:

• Planar formats:
  • YUV420p / I420 — 4:2:0, separate Y, U, V planes.
  • YV12 — 4:2:0 with swapped U/V plane order.
  • YUV422p / I422 — 4:2:2 planar.
  • YUV444p — full chroma resolution.
• Semi-planar formats:
  • NV12 — 4:2:0 with interleaved UV.
  • NV21 — 4:2:0 with interleaved VU.
• Packed formats:
  • UYVY / YUY2 — 4:2:2 packed (YUYV/YUY2 variants).
  • YVYU, VYUY — other byte-order packed variants.
• High-bit-depth and specialized formats (where supported):
  • YUV10 / 10-bit planar variants.
  • P010 / P016 — 10-/16-bit semi-planar used in HEVC/VVC workflows.
  • RGB preview/capture modes to display converted frames.

Color range and matrix handling

• Supports both full (0–255) and limited/TV (16–235) ranges for 8-bit sources; analogous ranges for higher bit depth.
• Recognizes common color matrices and transfer characteristics:
  • BT.601, BT.709, BT.2020 matrices for YUV-to-RGB conversion.
  • Basic handling of gamma/transfer expectations (sRGB, linear) for preview correctness.
• Option to manually override range and matrix when metadata is absent or incorrect.

Resolution, stride, and alignment

• Manual entry of width, height, and frame size/stride for raw inputs that lack headers.
• Options for per-plane stride and line padding to accommodate capture dumps from hardware or encoder outputs.
• Handling of odd widths/heights and chroma subsampling alignment rules (e.g., even width for 4:2:0 chroma).

Frame sequence and indexing

• Open multi-frame raw YUV sequences with configurable frame count and starting index.
• Frame stepping: single-step forward/back, jump to frame number, play/pause for quick review.
• Support for indexing via filenames when frames exported as sequential images.

Viewing and display settings

• Zoom and pan controls with nearest/linear interpolation options.
• Pixel aspect ratio (PAR) / display aspect ratio (DAR) override to view non-square pixels correctly.
• Overlay grid, frame number, timestamp, and per-channel visualization toggles:
  • Y-only, U-only, V-only.
  • Chrominance difference or combined RGB preview.
• False-color heatmaps for luma clipping and chroma range violations.

Color tools and measurement

• Per-pixel readout: Y, U, V, and converted RGB values under cursor.
• Histogram views for Y, U, V channels and combined luminance distribution.
• Waveform / vectorscope (where available) for broadcast-level compliance checks.
• Min/max/average luminance and chroma stats for current frame or sequence.

Export and conversion

• Export current frame to PNG/BMP (converted to RGB) with optional gamma correction.
• Dump selected frames back to raw YUV with chosen format (planar/packed, bit-depth).
• Save measurement data (histograms, per-frame stats) as CSV for offline analysis.

Performance and compatibility notes

• Works best for uncompressed, developer-oriented inspection; not a full media player for all codecs.
• For codec-wrapped sources (MP4, MKV), use FFmpeg to extract raw frames to a supported YUV format, then open in YUV Viewer.
• High-resolution and high–bit-depth files may require increased memory and disable real-time playback.

Typical workflows

1. Inspect a raw encoder output:
   • Open .yuv, set width/height, choose pixel format and range, step through frames to verify chroma placement and alignment.
2. Validate color conversion:
   • Toggle matrices (BT.709 vs BT.601) and compare RGB preview; use waveform/vectorscope to check broadcast limits.
3. Troubleshoot capture dumps:
   • Adjust per-plane stride, override byte order (UYVY vs YUY2), and inspect histograms for clipping or bit-shift artifacts.

Quick settings checklist (recommended defaults)

• Set width/height and pixel format on open.
• Choose correct color matrix (BT.709 for HD, BT.601 for SD).
• Select limited range for broadcast material, full range for computer graphics.
• Enable per-pixel readout and histogram for debugging.

If you want, I can provide step-by-step instructions for extracting frames with FFmpeg for a particular codec and opening them in YUV Viewer.