asset could not be parsed: Bad BMFF Other UnsupportedOperation('read')

[ttbuffey]

I used the version c2pa-python==0.6.1, when I upload a .mov video, it get this error.
Bad BMFF Other UnsupportedOperation('read')

code

       def private_sign(data: bytes) -> bytes:
            if isinstance(data, str):
                data = data.encode('utf-8')
            private_key = os.getenv("C2PA_PRIVATE_KEY")
            return sign_ps256(data, base64.b64decode(private_key))
        
        cert_chain = os.getenv("C2PA_CERT")
        signer = create_signer(private_sign, SigningAlg.PS256, base64.b64decode(cert_chain), "http://timestamp.digicert.com")
        print(signer)
        # Create a builder add a thumbnail resource and an ingredient file.
        
        builder = Builder(manifest)
        # Sign the builder with a stream and output it to a stream
        # This returns the binary manifest data that could be uploaded to cloud storage.
        input_stream = open(image_path, "rb")
        
        output_path = os.path.join(output_folder, 'embedded_Metadata'+file_extension)
        output_stream = open(output_path, "wb")
        c2pa_data = builder.sign(signer, mime_type, input_stream, output_stream)
        return output_path

[tmathern]

Does this happen with any mov video? Or only some?

[ttbuffey]

@tmathern i works for any video, then I modified the code to builder.sign_file(signer, image_path, output_path) not sign function, now it works.

[tmathern]

It's a bit hard to follow for me - does it work or not? Did you update to latest version (we improved BMFF support, and we're improving it still)?

[ttbuffey]

Hi @tmathern the code doesn't work for videos in c2pa-python==0.6.1. So I changed the function to sign_file, then it works for video.

Now I try to test the same code in the issue with the latest version - 0.120, but I can't find sign_ps256 with the below import code
from c2pa import Builder, C2paError as Error, Reader, C2paSigningAlg as SigningAlg, C2paSignerInfo, Signer, sdk_version
from c2pa.c2pa import Stream, read_ingredient_file, read_file, sign_file, load_settings, create_signer, sign_ps256

it give me error
cannot import name 'sign_ps256' from 'c2pa.c2pa',

how to import sign_ps256 in latest version?

[ttbuffey]

Also I tried the below code that doesn't contain sign_ps256, it also gives me error for a video.

c2pa-python version - 0.12.0

error message
Unexpected error: Other: asset could not be parsed: Bad BMFF Success (os error 0)

code

from c2pa import Builder, C2paError as Error, Reader, C2paSigningAlg as SigningAlg, C2paSignerInfo, Signer, sdk_version
from c2pa.c2pa import Stream, read_ingredient_file, read_file, sign_file, load_settings, create_signer
with open(cert_path, 'rb') as cert_file, open(key_path, 'rb') as key_file:
        private_key = key_file.read()
        cert_chain = cert_file.read()
        logger.info(f"cert_chain: {cert_chain}")  # Log the first 100 characters for brevity
        try:
            signer_info = C2paSignerInfo(
                alg=b"ps256",
                sign_cert=cert_chain,
                private_key=private_key,
                ta_url=b"http://timestamp.digicert.com"
            )
            signer = Signer.from_info(signer_info)
        except Exception as e:
            logger.error(f"Error creating signer: {e}")
            raise RuntimeError(f"Error creating signer: {e}") from e
        logger.info(f"signer created in {time.time()} duration {time.time() - starttime}")
        # Create a builder add a thumbnail resource and an ingredient file.
        builder = Builder(manifest)
        logger.info(f"builder finished in {time.time()} duration {time.time() - starttime}")

[tmathern]

sign_ps256 as standalone function is not part of c2pa-python anymore. The new way of doing that signing is the second version you show:

signer_info = C2paSignerInfo(
    alg=b"ps256",
    sign_cert=certs,
    private_key=private_key,
    ta_url=b"http://timestamp.digicert.com"
)
signer = Signer.from_info(signer_info)
builder = Builder(manifestDefinition)

(Or with a more custom callback signer).

Regarding the Bad BMFF issue, it can be two things:

• either we have a bugfix in the very latest native versions that fixes that (because I have passing video tests in this WIP PR feat: Bump to latest native libs version #140)
• or the video you're using to test has something "special" or an edge case. To determine that I would need to look at it (and possibly share with the Rust SDK team) - is it a video you could share, @ttbuffey ?

(As an aside, in your second snippet, code is missing, like the call to builder.sign(signer, "image/jpeg", source_file_as_stream, dest_file_as_stream) to actually sign. Note that the 2 last parameters should be opened files (as streams).

[ttbuffey]

Hi @tmathern please check this video,
https://github.com/user-attachments/assets/d4de7ae6-5fbb-48e3-a2a0-ec4e9a81749d

And for the aside issue, I forget to add the sign code, I used builder.sign_file function
c2pa_data = builder.sign_file(signer=signer, source_path=image_path, dest_path=output_path), I tried with different videos, it has the same error
Unexpected error: Other: asset could not be parsed: Bad BMFF Success (os error 0)

**when I switched to the code as you suggested for sign with builder.sign function **, the same error occurs.

with open(image_path, "rb") as source_file, open(output_path, "wb") as dest_file:
        manifest_bytes = builder.sign(signer, mime_type, source_file, dest_file)

[tmathern]

Thanks for the video, that helps! I tried it out with the changes from #140 and it worked. So once that one is released, your troubles should see an end!

Evidence is in that branch: https://github.com/contentauth/c2pa-python/tree/mathern/check-video (all tests should pass for you too if you run them).

[tmathern]

Fix published in https://pypi.org/project/c2pa-python/0.13.0/.
@ttbuffey If this is still not working for you, could you consider trying to write a unit test that reproduces the issue?

[ttbuffey]

@tmathern I tested the video works now with 0.15.0 now. The issue is fixed now.

I used the sign code
c2pa_data = builder.sign_file(signer=signer, source_path=image_path, dest_path=output_path)

But if I use the sign code

with open(image_path, "rb") as source_file, open(output_path, "wb") as dest_file:
        manifest_bytes = builder.sign(signer, mime_type, source_file, dest_file) 

it fails. though it's not affecting my features now, just let you know.
error message

error while attaching c2pa metadata: Other: hash verification( Asset hash failure: assertion.bmffHash.mismatch )