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Add T.35 metadata tool and SMPTE ST 2094-50 support#63

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podborski wants to merge 83 commits intomasterfrom
t35_tool
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Add T.35 metadata tool and SMPTE ST 2094-50 support#63
podborski wants to merge 83 commits intomasterfrom
t35_tool

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@podborski podborski commented Feb 10, 2026 •
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Adds comprehensive ITU-T T.35 metadata support to libisomediafile plus a new command-line tool for injecting/extracting SMPTE ST 2094-50 dynamic HDR metadata.

What's New

Library (libisomediafile):

  • New box types: it35 (T.35 sample entry), mebx (boxed metadata), colr (color info)
  • MEBX track APIs: ISONewMebxSampleDescription(), ISOAddMebxMetadataToSampleEntry()
  • Bug fix: QTFF keys box corruption in Apple-style meta containers

Tool (t35_tool):

  • Inject/extract T.35 metadata with multiple strategies (MEBX tracks, dedicated tracks, sample groups)
  • Full SMPTE ST 2094-50 encoder/decoder with JSON input/output
  • Auto-detection of metadata formats
  • Includes 11 test JSON files + test video

Usage:

  # Inject
  ./t35_tool inject input.mp4 output.mp4 --source smpte-folder:./json --method mebx-me4c

  # Extract
  ./t35_tool extract output.mp4 ./output --method auto

podborski and others added 30 commits April 22, 2025 17:01
@podborski
add MP4GetMovieIndTrackNALUnitLength API
864da46 
setup unit test
@podborski
Merge branch 'config_records' into t35
f9d7a6b
@podborski
ISOAddT35GroupDescription and other things
f6e0ab1
@podborski
when defragmenting an empty stts make sure to add the first entry
7289fca
@podborski
just go for it :)
48ff054
@podborski
add a simple test for T35 mebx
aeb5405
@podborski
initial implementation of t35_tool
fa9bb7f
@podborski
add ISOBMFF colr box implementation
20e426a 
for now I don't use the one from MJ2, we will need to figure out how to
    allow both implemenations to pass.
@podborski
use cli11 lib
0a47831
@podborski
demux mebx samples to binary blobs of data
0cfa797
@podborski
encapsulate into boxes when muxing, use trackreaders when deumxing
b21acf8
@podborski
this is not a bug, sorry for the noise
a6d718c
@podborski
API brushup, select mebx data based on key info
f58de9a
@podborski
dump NALUs from sample entry
cdcf1c6
@podborski
add CLI option to set T.35 prefix
d7670da
@podborski
initial implementatio of SEI injection
3d8c6ab
@podborski
use rndr track reference type
3d2f68d
Add inject and extract of SMPTE ST 2094-50 metadata from json file
c25f3b3
@podborski
Merge pull request #1 from img-standards/smpte_st_2094_50
5454552 
Add inject and extract of SMPTE ST 2094-50 metadata from json file
Fix gain max/span
df88959 
Trying to inject new mebx track
@podborski
put as text
4976c0c
@podborski
search for correct mebx track, never give up :)
eae66de
Fix headroom offset and scaling (application version = 1111)
754cbf0
Merge branch 't35_mebx' of https://github.pie.apple.com/img-standards…
40ef7f2 
…/isobmff-internal into t35_mebx
@podborski
write SEI T.35 header correctly
075f394
Update to use structure rather flat list and use latest version
2c07c9a
Add classes for SMPTE 2094-50 -> Inject only working
a4f581f
Update decoding
ee1e039
@podborski
Merge branch 'config_records' into t35
e8724ee
@podborski
Merge branch 'config_records' into t35
6706e9b
@podborski podborski changed the title T35 tool Add T.35 metadata tool and SMPTE ST 2094-50 support Feb 10, 2026
podborski and others added 19 commits February 10, 2026 12:21
@podborski
remove mebx with it35 namespace as it was not agreed at MPEG
9f91e6f
@podborski
remove t35C as it was not agreed at MPEG
8577419
@podborski
cleanup testdata for t35_tool
ba10ce1
@podborski
remove legacy code
aa38431
@podborski
test scripts updates
5c4c744
@podborski
me4c bugfix
0188969
@podborski
clangformat
a0f9457
ST2094-50 Remove extra byte when no headroom-adaptive tone mapping
f2a1183
Update SMPTE_ST2094_50.cpp
b7da55c 
Fix wrong condition for has_common_curve_params_flag at encoding
Reformat print of binary
@podborski
Merge branch 'master' of https://github.com/MPEGGroup/isobmff into t3…
83a6e12 
…5_tool
@podborski
update clang format stuff
7a4564f
@podborski
windows build fix
8454624
@podborski
fix tests
387cc66
@podborski
try fixing clang format thing
c6aa9d7
[ST2094-50] angle to slope metadata item update
3137a7c 
replace gainCurveControlPointTheta by gainCurveControlPointM and add conversion from slope to angle
Merge branch 't35_tool' of https://github.com/MPEGGroup/isobmff into …
760edb5 
…t35_tool
[ST2095-50] common flag check fix
2f96263 
Fix flag checking (got overwrote by last merge)
Fix extract looging format
Dedicated-it35 Fix close media edits
5aff53c 
Missing closing mediaEdits
[ST2094-50] Fix at decode scaling of component mix when not equal to 1.0
9f176cb 
Quantization can result in sum of quantized value not equal to 50000 (1.0). Scaling by the sum of all custom coefficient.
Also fixed wrong common flag set at encode.
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2 participants

@podborski @y-guyon