OggIssues
Seeking and Editing Problems
- jagged edges
- wide variance in location of cotemporal data
- impossible to reconstruct all granulepos values around holes
- granulepos / timeval mapping inconsistencies
- poorly sorted streams are rife
- impossible to efficiently seek with noncontinuous data
Other Niggles
- end-time ordering
- except when we have non-continuous data
- inefficient lacing values for video
- ad-hoc granulepos retrofitting for video, CMML
- seeking is hard
- pages, and libogg's behaviour when creating them
i don't know the answers
- We need to design a successor to Ogg
- It should be called (Ogg2|Ogg3|Ogg++|OggNG|Ogh|Foo|Dumplings)
- The design should be done from desired capabilities and desired properties
- These capabilities and properties should come from AV experts, web-page designers, system administrators, and users
Desired Capabilities
- Simple seeking
- Cleanly cuttable
- Robust to errors
- Composable
- Supports arbitrary stream types
- Low bit cost
- Streamable
- Easy to chunk
- Low decode cost
- Supports multiple streams of each type
Untied We Stand
- Can cotemporal data be colocated?
- streams & bundles
- great for cutting
- OK for demultiplexing
- “should” cut down on bit overhead
- hugely simplifies seeking
Gimme a Hint
- Can we add seeking hints to the stream?
- these can be tiny and infrequent
- awesome for standalone files
- what do we do when streaming?
- hint correction packets?
- is this turtles all the way down?
- Would an up-front index be better?
Cleaner Abstractions
- We should not need to know the type of a stream if we are not decoding the stream
- granulepos interpretations
- headers
- seeking
- cutting
- Skeleton goes some way towards fixing this
What use are...
- serial numbers?
- packet numbers?
- pages?
- checksums?
Devil's Advocate
- These problems aren't unsurmountable
- but we're only finding some of them now, and we've been working around others for years
- Nobody will adopt another container format
- Nobody cares about <insert hated feature here> anyway