JVET-AN0017 JVET AHG report: Testing of video coding technology beyond CTC (AHG17) [J.-R. Ohm, M. Wien, F. Bossen (co-chairs), M. Abdoli, E. Alshina, V. Baroncini, J. Chen, R. Chernyak, Z. Deng, P. de Lagrange, L. Li, P. Nikitin, D. Rusanovskyy (vice chairs)]

1. Activities

The draft CfE document JVET-AM2026 was finalized and uploaded to the JVET document site. The test sequences for all categories defined in the CfE document were collected in a dedicated folder on the JVET content server.

Four online AHG calls were held on 2025-07-29, 2025-08-21, 2025-09-11, and 2025-09-29, respectively. The reports of these meetings are available in JVET-AN0041.

1. Preparation of bitstreams according to the CfE conditions

The categories of the draft CfE include:

• SDR RA UHD/4K: Representing the use case of distribution of standard dynamic range UHD/4K video content e.g. in a streaming scenario, using a random-access configuration.
• SDR RA HD: Representing the use case of distribution of standard dynamic range HD video content e.g. in a streaming scenario, using a random-access configuration.
• SDR LB HD: Representing the use case of conversational and other low delay applications at HD resolution, correspondingly using a low-delay configuration.
• HDR RA 4K: Representing the use case of distribution of high dynamic range UHD/4K video content e.g. in a streaming scenario, using a random-access configuration.
• HDR RA Cropped 8K: Representing the use case of distribution of high dynamic range 8K video content e.g. in a streaming scenario, using a random-access configuration. In order to reduce the encoding workload for assessment of this category and allow investigation on 4K displays, cropped regions of 3840×2160 resolution are used.
• Gaming LB HD: Representing the use case of online gaming with a low-delay configuration.
• UGC RA: Representing the use case of user generated content at 1080×1920 or 1920×1080 resolution using a random-access configuration.

For all categories, test sequences and corresponding target rates are specified in JVET-AM2026. VTM anchor bitstreams as well as ECM bitstreams matching the target bitrates for study of improved compression performance were generated. Furthermore, for the study of reduced complexity encoding, bitstreams for the following encoder configurations were generated:

• VTM RT1: VTM with reduced runtime setting at about 65% of the runtime of the default VTM configuration;
• VTM RT2: VTM with reduced runtime setting at about 50% of the runtime of the default VTM configuration;
• VTM RT3: VTM with reduced runtime setting at about 25% of the runtime of the default VTM configuration;
• ECM 2x: ECM with a reduced runtime setting at about a factor of 2 of the runtime of the default VTM configuration.
• ECM 5x: ECM with a reduced runtime setting at about a factor of 5 of the runtime of the default VTM configuration.

1. Planning for on-site viewing sessions

For conduction of the viewing tests, the AHG recommended all proposals submitted for the compression efficiency test case (CP) to be evaluated. For the runtime test case (RT), a selected subset was recommended in the last AHG. With this selection, 686 test points (“processed video sequences”, PVS) are to be evaluated for the CP case and 1088 test points are to be evaluated for the RT case.

A test including 12 test sessions for CP and 21 test sessions for RT was designed. The sessions separate PVS in HDR PQ, HDR HLG, SDR UHD, and SDR HD 50/60fps for smooth playout purposes. The suggested allocation of the test efforts is as follows:

For each session, 24 volunteers are requested to participate. A email requesting for registration for the sessions will be sent out at the beginning of the JVET meeting.

1. Related contributions

It is noted that multiple documents have partial allocation to AHG17 and other AHGs. This includes JVET-AN0053, JVET-AN0157, JVET-AN0177, JVET-AN0189, JVET-AN0190.

1. Expression of thanks

All volunteers for the efforts of bitstream generation and reporting of metrics were thanked. Frank Bossen was thanked for crosschecking bitstreams and CSV files. Mathias Wien was thanked for preparing the viewing tests.

1. Recommendations

The AHG recommended:

• To conduct subjective tests assessing the proposed rate points and coding conditions in the draft CfE.
• To study the results of the visual tests and conclude on the findings.
• To review the remaining input contributions related to AHG17 during the meeting.

It was suggested to add a viewing session related to the CfE contribution on ULD/ER functionality (last session Monday).

First presentation of results planned for Tuesday (late, e.g. 1900).