HLS — Intentionally Corrupt: Missing #EXTM3U Signature
An intentionally corrupt HLS playlist with the mandatory #EXTM3U signature removed. Everything else is valid. The specification requires the first line to be exactly #EXTM3U and that clients reject anything else, so this separates conforming parsers from lenient ones that sniff for EXT tags instead.
#EXT-X-VERSION:7
#EXT-X-TARGETDURATION:4
#EXT-X-PLAYLIST-TYPE:VOD
#EXTINF:4.000,
seg-00001.m4s
#EXTINF:4.000,
seg-00002.m4s
#EXT-X-ENDLIST
Specifications
- Corruption
- missing mandatory #EXTM3U first line
- Otherwise Valid
- yes
- Segments
- 2
What is a .m3u8 file?
M3U8 (.m3u8) is a UTF-8 M3U playlist, most importantly the backbone of HTTP Live Streaming (HLS). An HLS media playlist lists timed media segments with #EXTINF tags and directives like #EXT-X-TARGETDURATION, and a master playlist points to alternate bitrate renditions.
How to use this file
Use an example .m3u8 file to test HLS parsers and players, segment and directive extraction, and adaptive-streaming tooling, or as a plain UTF-8 M3U playlist.
How to use this file for testing
“HLS — Intentionally Corrupt: Missing #EXTM3U Signature” is a deterministic Novus Examples fixture for Streaming manifests, Video QA. HLS playlists and DASH MPDs covering multi-bitrate ladders, byte-range addressing, and segment templates. Served inline with permissive CORS under /files/stream/, so a player can load them from any origin without re-hosting.
Documented properties for this file: M3U8 · 139 bytes. 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.
Code examples
# manifests resolve their own segments, so pass the URL, not a local copy
ffprobe -v error -show_entries stream=codec_name,width,height no-extm3u.m3u8
ffplay no-extm3u.m3u8Related files
- mpdDASH — Dynamic (Live) Manifest With a Time-Shift BufferA live DASH manifest: type is dynamic, there is no total duration, and the client must compute which segment is currently available from availabilityStartTime, the wall clock, and the segment duration. Declares a one-minute time-shift buffer and an eight-second presentation delay. The timestamps are fixed so the fixture stays deterministic — a real client will compute a segment number far in the future, which is itself a useful edge case to handle gracefully.

- mpdDASH — Explicit SegmentList AddressingThe same content addressed with an explicit SegmentList — every segment URL enumerated rather than derived from a template. Verbose, but it is what older packagers emit and it permits non-uniform segment naming. A DASH client must support both this and SegmentTemplate; the paired template manifest in this group is the direct contrast.

- mpdDASH — Multi-Period Manifest With a Mid-Roll BreakThree DASH periods — content, an ad break, then content again — each with its own initialisation segment. Period boundaries are where players most often break: the decoder must be reset, the buffer cannot span the discontinuity, and rendition selection restarts. Pairs with the VMAP and SCTE-35 fixtures, which describe the same break from the ad-signalling side.

- mpdDASH — Static MPD With a Segment TemplateA DASH manifest with separate video and audio adaptation sets, three video representations, and $RepresentationID$/$Number$ segment-template addressing — the standard VOD packaging shape. Served inline as application/dash+xml with permissive CORS, so dash.js can load it cross-origin. A manifest-parsing fixture: it describes segment URLs rather than shipping the segments.

- m4sDASH VOD — Init Segment (init-stream0.m4s)A DASH initialisation segment carrying codec configuration for one representation. Named by the manifest's $RepresentationID$ template, so this file also exercises whether a client resolves template variables correctly rather than pattern-matching filenames.

- m4sDASH VOD — Init Segment (init-stream1.m4s)A DASH initialisation segment carrying codec configuration for one representation. Named by the manifest's $RepresentationID$ template, so this file also exercises whether a client resolves template variables correctly rather than pattern-matching filenames.

Generated by generation/video_timedtext.py. Free for any use, no attribution required — license.