netflix / vp9-dash

VP9 ISO-BMFF Packaging Specification and sample files

vp9-dash

The official specification for the binding of VP9 streams to ISOBMFF is available here

vp9-dash's Issues

Sample vs Frame

Can you clarify what the following sentence mean ?

Video sample storage in the generic binding uses a simple mapping to frames defined in the codec
specification.
Does it mean the sample data corresponds to the frame() syntactical element from the spec?

Need to replace the PDF with a Word Doc

In order to facilitate edits and change tracking, need to shift from PDF to Word doc.

where to get the @frameRate information

The DASH IF Interoperability Points (3.3) require that the @framerate attribute to be set. I do not see this signaled in any way in the VP codec binding. For AVC/HEVC this can be retrieved from the VisualSampleEntry (one way or another). Is there a way to get this for VP as well?

color properties precedence

Hi,
this specification sets color properties (space, transfer and primaries) in the vpcC.

Would it be possible to use the standard colr instead? It would simplify tooling since parsing of this box is well implemented in most video players and it would speed up the adoption of this standard.

If not, could you add a line indicating which box has the precedence, and what to do if there is a mismatch between vpcC, colr and bitstream values?

Thanks.

chromaSubsampling value typo

chromaSubsampling is an integer that specifies the chroma sub sampling. Only the values in the following table are specified. If colorspace is 4 (RGB), then chroma subsampling must be 4 (4:4:4).

The table above reports that colorspace 4 is SMPTE-240, the value should probably be 7 (sRGB).

(spotted by @justinruggles)

Please add sample files.

Hi. Could you please upload some sample files? It would help to have something to test my implementation against.

Supported players

Hi,

Two questions -

1. Which players support these files ? is Shaka player expected to support it ?
2. Any chance you can add the MPD files that go with these fragmented MP4s ?

Thank you !

Eran

Encryption of superframes

For encryption of superframes, the document states that 'the superframe header must be clear'. Shouldn't this be the superframe_index() instead?

Definition of VPCodecConfigrationRecord.level

It's not clear to me where to find the value for the VPCodecConfigrationRecord.level field as it doesn't seem to match to any existing setting of the libvpx encoder API. The samples in DASH-Samples/ all have a level value of 0. Is this something new for the VP10 encoder, or am I missing something?

Specifying the "subs" subsample-information box

Since the encryption for VP is specified to use Subsample Encryption, is there also a specification for the "subs" box (similar to AVC)? In VP's case, a frame is a single subsample, and a superframe would have multiple subsamples (ALTREF frames).