【obs-studio开源项目从入门到放弃】obs高级输出内存泄露

文章目录

前言
FFmpeg高级输出内存泄露
内存泄露原因
解决办法

前言

obs系列文章入口：obs-studio项目简介和架构

FFmpeg高级输出内存泄露

已解决
PR: obs-ffmpeg: Fix ffmpeg_output memory leak

obs高级输出的介绍：【obs-studio开源项目从入门到放弃】obs 的高级输出 ffmpeg-output

最近长时间推流测试发现，obs的高级输出存在内存泄露。泄露速度不是很快，大约每分钟泄露1M多内存，12个小时泄露700多M。但是如果长时间录制或者使用FFmpeg高级输出推流，会因内存泄露导致崩溃。

内存泄露原因

obs-ffmpeg-output.c 在 receive_video() 和 receive_audio() 都调用了av_packet_alloc() 来申请 AVPacket 内存空间，但是在process_packet() 使用完 AVpacket后，并没有调用 av_packet_free() 来释放内存，因此会产生内存泄露。

解决办法

修改源码 obs-ffmpeg-output.c av_interleaved_write_frame 使用完 packet后，调用 av_packet_free() 释放 packet的内存。

static int process_packet(struct ffmpeg_output *output)
{AVPacket *packet;bool new_packet = false;int ret;pthread_mutex_lock(&output->write_mutex);if (output->packets.num) {packet = output->packets.array[0];da_erase(output->packets, 0);new_packet = true;}pthread_mutex_unlock(&output->write_mutex);if (!new_packet)return 0;/*blog(LOG_DEBUG, "size = %d, flags = %lX, stream = %d, ""packets queued: %lu",packet.size, packet.flags,packet.stream_index, output->packets.num);*/if (stopping(output)) {uint64_t sys_ts = get_packet_sys_dts(output, packet);if (sys_ts >= output->stop_ts)return 0;}output->total_bytes += packet->size;ret = av_interleaved_write_frame(output->ff_data.output, packet);if (ret < 0) {//av_packet_free(&packet); //此处注释掉ffmpeg_log_error(LOG_WARNING, &output->ff_data,"process_packet: Error writing packet: %s",av_err2str(ret));return ret;}//=== 解决内存泄露：释放 packet 内存===av_packet_free(&packet);//===================================return 0;
}

av_packet_alloc 和 av_packet_free 源码

/*** Allocate an AVPacket and set its fields to default values.  The resulting* struct must be freed using av_packet_free().** @return An AVPacket filled with default values or NULL on failure.** @note this only allocates the AVPacket itself, not the data buffers. Those* must be allocated through other means such as av_new_packet.** @see av_new_packet*/
AVPacket *av_packet_alloc(void)
{AVPacket *pkt = av_malloc(sizeof(AVPacket));if (!pkt)return pkt;get_packet_defaults(pkt);return pkt;
}/*** Free the packet, if the packet is reference counted, it will be* unreferenced first.** @param pkt packet to be freed. The pointer will be set to NULL.* @note passing NULL is a no-op.*/
void av_packet_free(AVPacket **pkt)
{if (!pkt || !*pkt)return;av_packet_unref(*pkt);av_freep(pkt);
}