nx_mp4_stbl.nx
buildroot/runtime/nx_mp4_stbl.nx
about
nx_mp4_stbl.nx -- MP4 sample-table reader (real-video bridge rung 1).
Descends a video track to stbl and reads: the CODEC (stsd first-entry fourCC),
the frame/sample COUNT (stsz), uniform sample size, and chunk count (stco).
This is the bridge between "there is a video track" (demux, rung 0) and the
coded frame byte ranges the codec decoder will consume (rung 2+).
It NAMES the codec: avc1/avc3=H.264, hev1/hvc1=H.265, vp09=VP9, av01=AV1,
mp4a=AAC. Pointed at a real recording, this reports exactly what codec the
capture used -- the fact the decode arc must target. Reuses nx_mp4_demux
box primitives. ISO/IEC 14496-12 sec.8 (stbl/stsd/stsz/stco).
genealogy_id: iso_bmff_sample_table + stsd_codec_identification
lineage_id: stbl_descent + fourcc_classify + sample_count
license_tier: ORIGINAL
dependencies 2 imports · 9 importers
imports: nx_syscalls.nxnx_mp4_demux.nx
imported by: nx_h264_decode_frame.nxnx_h264_mv_recon_gate.nxnx_h264_pframe_probe.nxnx_h264_pframe_recon.nxnx_h264_pframe_walk.nxnx_h264_slice_extract.nxnx_mp4_es.nxnx_mp4_real_probe.nxnx_mp4_stbl_gate.nx
structs
| none |
consts
| 18 | const NX_CODEC_OTHER: i64 = 0 |
| 19 | const NX_CODEC_H264: i64 = 1 |
| 20 | const NX_CODEC_H265: i64 = 2 |
| 21 | const NX_CODEC_VP9: i64 = 3 |
| 22 | const NX_CODEC_AV1: i64 = 4 |
| 23 | const NX_CODEC_AAC: i64 = 5 |
functions
| 25 | func nx_mp4_codec_class(b: *u8, o: i64) -> i64 |
| 38 | func nx_mp4_parse_stbl(b: *u8, start: i64, end: i64, out: *i64) -> i64 |
| 59 | func nx_mp4_video_info(b: *u8, len: i64, out: *i64) -> i64 |