【 vb2_buffer_state】 v4l2 videobuf的几种状态
发布时间:2020-12-17 08:03:11 所属栏目:百科 来源:网络整理
导读:http://lxr.free-electrons.com/source/include/media/videobuf2-core.h#L164 142 /** 143 * enum vb2_buffer_state - current video buffer state 144 * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control 145 * @VB2_BUF_STATE_PREPARED: buffer p
http://lxr.free-electrons.com/source/include/media/videobuf2-core.h#L164
142 /** 143 * enum vb2_buffer_state - current video buffer state144 * @VB2_BUF_STATE_DEQUEUED: buffer under userspace control 145 * @VB2_BUF_STATE_PREPARED: buffer prepared in videobuf and by the driver 146 * @VB2_BUF_STATE_QUEUED: buffer queued in videobuf,but not in driver 147 * @VB2_BUF_STATE_ACTIVE: buffer queued in driver and possibly used 148 * in a hardware operation 149 * @VB2_BUF_STATE_DONE: buffer returned from driver to videobuf,but 150 * not yet dequeued to userspace 151 * @VB2_BUF_STATE_ERROR: same as above,but the operation on the buffer 152 * has ended with an error,which will be reported 153 * to the userspace when it is dequeued 154 */ 155 enum vb2_buffer_state { 156 VB2_BUF_STATE_DEQUEUED, 157 VB2_BUF_STATE_PREPARED, 158 VB2_BUF_STATE_QUEUED, 159 VB2_BUF_STATE_ACTIVE, 160 VB2_BUF_STATE_DONE, 161 VB2_BUF_STATE_ERROR, 162 };
出队 dequeue,缓冲已经进入了用户控件。 准备好了,prepared,驱动管辖着把缓冲放在了videobuf中。 入队了,queued,缓冲进入了videobuf中了,已经不在驱动管辖下。 激活,active,缓冲已经在驱动中了,并可能已经在硬件操作中被使用了。 完成,DONE,缓冲已经从驱动到了videobuf中,但还没有进入dequeue到用户空间中。 错误,error,缓冲已经从驱动到了videobuf中,但还没dequeue进入到用户空间中,但是呢,对于缓冲的操作遇到了错误,当dequeue到用户空间的时候,会汇报错误。 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |