copy of an AVPacket structure

a copy of an AVPacket structure

参考：https://stackoverflow.com/questions/12929330/create-a-copy-of-an-avpacket-structure

ok：

AVPacket newPacket(oldPacket);
newPacket->data = reinterpret_cast<uint8_t*>(new uint64_t[(oldPacket->size + FF_INPUT_BUFFER_PADDING_SIZE)/sizeof(uint64_t) + 1]);
memcpy(newPacket->data, oldPacket->data, oldPacket->size);

    AVPacket *newpacket = (AVPacket*)malloc(sizeof(struct AVPacket));
        av_init_packet(newpacket);
        av_packet_ref(newpacket, packet);

        av_packet_unref(packet);
        free(packet);
        packet = nil;