View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0000057 | JVT JM H.264/AVC reference software | decoder | public | 2007-06-07 13:32 | 2010-04-22 16:07 |
| Reporter | Karsten Suehring | Assigned To | Karsten Suehring | ||
| Priority | normal | Severity | minor | Reproducibility | always |
| Status | resolved | Resolution | fixed | ||
| Platform | any | ||||
| Product Version | JM 12.2 | ||||
| Fixed in Version | JM 17.1 | ||||
| Summary | 0000057: delta_pic_order_cnt[0] in IDR frames | ||||
| Description | "zhang" reported: We have a problem about delta_pic_order_cnt[0]. If the current picture is an IDR picture, JM will ignore delta_pic_order_cnt[0] value in slice header and force set it as 0. In some bitstream we will get (TopFieldOrderCnt, BottomFieldOrderCnt) = (0, -5) from JM. This picture is an IDR picture but it seems to violate the definition in H.264 specifiction, 8.2.1. The bitstream shall not contain data that results in Min( TopFieldOrderCnt, BottomFieldOrderCnt ) not equal to 0 for a coded IDR frame, TopFieldOrderCnt not equal to 0 for a coded IDR top field, or BottomFieldOrderCnt not equal to 0 for a coded IDR bottom field. Thus, at least one of TopFieldOrderCnt and BottomFieldOrderCnt shall be equal to 0 for the fields of a coded IDR frame. The source code shows as follows File: image.c Function: decode_poc case 1: // POC MODE 1 // 1st if(img->idr_flag) { img->FrameNumOffset=0; // first pix of IDRGOP, img->delta_pic_order_cnt[0]=0; //ignore first delta if(img->frame_num) error("frame_num not equal to zero in IDR picture", -1020); } In our thought, we will get (TopFieldOrderCnt, BottomFieldOrderCnt) = (5, 0) -- (we don't force delta_pic_order_cnt[0] as 0 when IDR picture). This result seems to be correct for the above definition in specification. Is this condition is my mis-understanding or there is a problem in JM ? Thanks a lot. | ||||
| Tags | No tags attached. | ||||
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2007-06-07 13:32 | Karsten Suehring | New Issue | |
| 2007-08-08 14:21 | Karsten Suehring | Status | new => assigned |
| 2007-08-08 14:21 | Karsten Suehring | Assigned To | => Karsten Suehring |
| 2007-08-08 14:22 | Karsten Suehring | Note Added: 0000093 | |
| 2010-04-22 16:07 | Karsten Suehring | Note Added: 0000356 | |
| 2010-04-22 16:07 | Karsten Suehring | Status | assigned => resolved |
| 2010-04-22 16:07 | Karsten Suehring | Fixed in Version | => JM 17.0-dev |
| 2010-04-22 16:07 | Karsten Suehring | Resolution | open => fixed |
