[音视频] avcodec_send_packet 返回-22

* @retval 0                 success
 * @retval AVERROR(EAGAIN)   input is not accepted in the current state - user
 *                           must read output with avcodec_receive_frame() (once
 *                           all output is read, the packet should be resent,
 *                           and the call will not fail with EAGAIN).
 * @retval AVERROR_EOF       the decoder has been flushed, and no new packets can be
 *                           sent to it (also returned if more than 1 flush
 *                           packet is sent)
 * @retval AVERROR(EINVAL)   codec not opened, it is an encoder, or requires flush
 * @retval AVERROR(ENOMEM)   failed to add packet to internal queue, or similar
 * @retval "another negative error code" legitimate decoding errors
int avcodec_send_packet(AVCodecContext *avctx, const AVPacket *avpkt);