提供用于编码视频数据之技术及系统。举例而言，对某些预测模式之限制可应用于视频写码。当满足某些条件时，可强加防止对视频数据运行框间预测双向预测之限制。举例而言，双向预测限制可基于是否对视频数据之一或多个写码单元或区块激活块内复制预测、语法元素之值是否指示一或多个运动矢量处于非整数准确度、双向预测区块之两个运动矢量是否皆处于非整数准确度、双向预测区块之运动矢量是否不相同及/或不来自同一参考索引或其任何组合。若满足此等条件中之一或多项，则可应用对双向预测之限制，以防止对某些写码单元或区块运行双向预测。

Techniques and systems are provided for encoding video data. For example, restrictions on certain prediction modes can be applied for video coding. A restriction can be imposed that prevents inter-prediction bi-prediction from being performed on video data when certain conditions are met. For example, bi-prediction restriction can be based on whether intra-block copy prediction is enabled for one or more coding units or blocks of the video data, whether a value of a syntax element indicates that one or more motion vectors are in non-integer accuracy, whether both motion vectors of a bi-prediction block are in non-integer accuracy, whether the motion vectors of a bi-prediction block are not identical and/or are not from the same reference index, or any combination thereof. If one or more of these conditions are met, the restriction on bi-prediction can be applied, preventing bi-prediction from being performed on certain coding units or blocks.