OpenRTB相关资料 文档 OpenRTB API Specification Version 2.5 FINAL OpenRTB Dynamic Native Ads API Specification Version 1.1 VIDEO AD SERVING TEMPLATE (VAST) VERSION 3.0 Digital Video Ad Serving Template (VAST) Version 2.0 Video Ad Serving Template (VAST) VERSION 4.0 OpenRTB Dynamic Native Ads API Specification Version 1.2 Final Version July 2017 OpenRTB Advisory - GDPR Fixed Size Ad Specifications IAB NEW STANDARD AD UNIT PORTFOLIO 工具 TECH LAB vast inspector