Convert v2 RealMedia Motion Source
RealMedia container with a short deterministic RealVideo motion pattern for download-only legacy demux and transcode coverage. Stable P8 artifact p8-convert-legacy-rm.
| property | expected |
|---|---|
| codec | RealVideo 1.0 |
| resolution | 160x128 |
| fps | 10 |
Specifications
- Codec
- RealVideo 1.0
- Resolution
- 160x128
- Fps
- 10
- Delivery Mode
- download-only
- Provider
- converter-v2
- Provenance
- Synthetic deterministic P8 fixture generated by generation/p8_content.py; seed namespace 2026082300
- Fixture Reserve
- convert-v2
Testing contract
Expected to pass- Scenario
- Demux the RM container, decode all video frames, and transcode to a browser format.
- Expected result
- A 160x128 RealVideo 1.0 stream at 10 fps decodes with a moving white box and produces a nonempty browser-playable output.
What is a .rm file?
RM is the RealMedia container developed for early streaming audio and video. A file consists of typed objects for the file header, properties, media streams, content metadata, packet data, and an optional index; the contained RealAudio or RealVideo codecs are separate from the container and are rarely browser-playable today.
How to use this file
Use a compact example .rm file to test container signature and object-length parsing, stream and duration metadata, truncated-object handling, and download-only fallback without claiming native browser playback.
How to use this file for testing
“Convert v2 RealMedia Motion Source” is a deterministic Novus Examples fixture for Conversion testing, Video codecs. The same content exported across many formats and linked as a group, so you can convert one and diff against the expected twin.
Documented properties for this file: 10 fps. Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.
Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such — expect parsers to fail loudly rather than silently accept them.
Media fixtures are short and synthetic by design. Prefer waveform or transcript ground truth in the same group when measuring ASR, trim, upscale, or sync tools; do not assume broadcast-quality masters.
Related files
- webmAlpha Channel — Opaque VP9 TwinThe same codec and container with NO alpha plane, as the control for the alpha clip in this group. Useful for checking that alpha detection reads the pixel format rather than assuming every WebM is transparent — and for confirming a compositing bug is in the alpha handling rather than in the player.
- webmAlpha Channel — VP9 in WebMVideo with a real per-pixel alpha channel: VP9 yuva420p in WebM, the one alpha path browsers decode natively. Composite it over a page background and the transparency is genuine, not a chroma key. Roughly 90% of each frame is fully transparent. Two traps this file exists to expose. First, auto-alt-ref must be disabled at encode time or libvpx silently drops the alpha plane, producing a valid file with no transparency and no error. Second, WebM stores VP9 alpha in BlockAdditional and signals it with AlphaMode=1, so FFmpeg's NATIVE vp9 decoder reports pix_fmt yuv420p and decodes fully opaque — you must force `-c:v libvpx-vp9` to see the alpha at all. Probing this file with default settings and concluding it has no alpha is the expected mistake.
- mp4Bitstream — All-Intra (Every Frame a Keyframe)Every frame is an I-frame, so any frame is an independent cut point. Much larger, and the shape editing and frame-accurate seeking want. Same picture and same codec as every other clip in this group — only the GOP and frame-type structure differ, so the effect on size and seekability is directly attributable.
- mp4Bitstream — Heavy B-Frames (8 Consecutive)Eight consecutive B-frames with a B-pyramid, so decode order and display order diverge sharply and DTS runs well behind PTS. The case that breaks naive timestamp handling and any code that assumes frames arrive in display order. Same picture and same codec as every other clip in this group — only the GOP and frame-type structure differ, so the effect on size and seekability is directly attributable.
- mp4Bitstream — Long GOP (24 Frames, One Per Second)One keyframe per second — the delivery default, and the setting that determines HLS/DASH segment boundaries, since a segment must start on a keyframe. Same picture and same codec as every other clip in this group — only the GOP and frame-type structure differ, so the effect on size and seekability is directly attributable.
- mp4Bitstream — No B-FramesI and P frames only. Required by some low-latency and legacy decoders, and it removes the reordering that makes decode order differ from display order. Same picture and same codec as every other clip in this group — only the GOP and frame-type structure differ, so the effect on size and seekability is directly attributable.
Generated by generation/p8_content.py. Free for any use, no attribution required — license.