fix: CEA-708 segmentation faults on MP4 files

[hrideshmg]

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---

Certain MP4 files under the general category have been segfaulting on the sample platform. The cause was a null pointer dereference in an unsafe rust block here.

The issue was that this particular variable is populated quite late in the MP4 processing chain and hence is sometimes missed. I've modified the code so that its populated right after declaration to fix it.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on linux. Below is a summary of the test results, when compared to test for commit 6300bb7...:

Report Name	Tests Passed
Broken	13/13
CEA-708	13/14
DVB	7/7
DVD	0/3
DVR-MS	2/2
General	25/27
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	85/86
Teletext	21/21
WTV	13/13
XDS	33/34

NOTE: The following tests have been failing on the master branch as well as the PR:

• ccextractor --service 1 --out=txt f17524b53f..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 5ae2007a79..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 1e44efd810..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 add511677c..., Last passed:

  Never

• ccextractor --autoprogram --out=srt --latin1 e9b9008fdf..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 27e46255f0..., Last passed:

  Never

• ccextractor --in=ps e9b9008fdf..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 --ucla --xds 0069dffd21..., Last passed:

  Never

Congratulations: Merging this PR would fix the following tests:

• ccextractor --autoprogram --out=ttxt --latin1 1974a299f0..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 132d7df7e9..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 99e5eaafdc..., Last passed: Never
• ccextractor --unicode c83f765c66..., Last passed: Never

All tests passing on the master branch were passed completely.

Check the result page for more info.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on windows. Below is a summary of the test results, when compared to test for commit 6300bb7...:

Report Name	Tests Passed
Broken	13/13
CEA-708	13/14
DVB	4/7
DVD	0/3
DVR-MS	2/2
General	25/27
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	85/86
Teletext	21/21
WTV	10/13
XDS	33/34

Your PR breaks these cases:

• ccextractor --out=srt --latin1 10f0f77cf4...

NOTE: The following tests have been failing on the master branch as well as the PR:

• ccextractor --service 1 --out=txt f17524b53f..., Last passed:

  Never

• ccextractor --stdout --quiet --no-fontcolor 79a51f3500..., Last passed:

  Never

• ccextractor --stdout --quiet --no-fontcolor 767b546f96..., Last passed:

  Never

• ccextractor --autoprogram --out=srt --latin1 --quant 0 85271be4d2..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 5ae2007a79..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 1e44efd810..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 add511677c..., Last passed:

  Never

• ccextractor --autoprogram --out=srt --latin1 e9b9008fdf..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 27e46255f0..., Last passed:

  Never

• ccextractor --in=ps e9b9008fdf..., Last passed:

  Never

• ccextractor --out=srt --latin1 f23a544ba8..., Last passed:

  Never

• ccextractor --out=srt --latin1 df3b4d62d3..., Last passed:

  Never

• ccextractor --autoprogram --out=ttxt --latin1 --ucla --xds 0069dffd21..., Last passed:

  Never

Congratulations: Merging this PR would fix the following tests:

• ccextractor --autoprogram --out=srt --latin1 f1422b8bfe..., Last passed: Never
• ccextractor --datapid 5603 --autoprogram --out=srt --latin1 --teletext 85c7fc1ad7..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 1974a299f0..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 132d7df7e9..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 99e5eaafdc..., Last passed: Never
• ccextractor --out=spupng c83f765c66..., Last passed: Never
• ccextractor --unicode c83f765c66..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 c0d2fba8c0..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 006fdc391a..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 e92a1d4d2a..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 7e4ebf7fd7..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 9256a60e4b..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 27d7a43dd6..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 297a44921a..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 efbe129086..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 eae0077731..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 e2e2b501e0..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 c6407fb294..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 --datets dcada745de..., Last passed: Never
• ccextractor --autoprogram --out=srt --latin1 --tpage 398 5d5838bde9..., Last passed: Never
• ccextractor --autoprogram --out=srt --latin1 --teletext --tpage 398 3b276ad8bf..., Last passed: Never

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Check the result page for more info.

[prateekmedia]

LGTM!