version
#define LIBSWRESAMPLE_VERSION_MAJOR 2
#define LIBSWRESAMPLE_VERSION_MINOR 9
#define LIBSWRESAMPLE_VERSION_MICRO 100
#define LIBAVCODEC_VERSION_MINOR 31
#define LIBAVCODEC_VERSION_MICRO 102
code
void CFfmpegOps::EncodePCMToAAC(const char *pcm_file, const char *aac_file)
{
AVFormatContext *fmt_ctx = nullptr;
const AVOutputFormat *out_fmt = nullptr;
int ret = -1;
AVStream *avstream = nullptr;
const AVCodec *codec = nullptr;
AVCodecContext *codec_ctx = nullptr;
AVFrame *avframe = nullptr; // pcm file对应的avframe
AVFrame *codec_avframe = nullptr; // 编码器接收的avframe
AVPacket *avpacket = nullptr;
int frame_data_bytes = 0;
FILE *in_fp = nullptr;
size_t n = 0;
int64_t pts = 0;
struct SwrContext *swr_ctx = nullptr; // 音频帧转换器
AVChannelLayout src_channel_layout;
AVChannelLayout dest_channel_layout;
codec = avcodec_find_encoder(AV_CODEC_ID_AAC);
if (!codec)
{
printf("avcodec_find_encoder error\n");
goto END;
}
codec_ctx = avcodec_alloc_context3(codec);
if (!codec_ctx)
{
printf("avcodec_alloc_context3 error\n");
goto END;
}
codec_ctx->sample_fmt = AV_SAMPLE_FMT_FLTP; // 编码器的接受的采样格式
codec_ctx->sample_rate = 44100;
codec_ctx->channel_layout = AV_CH_LAYOUT_STEREO;
codec_ctx->channels = av_get_channel_layout_nb_channels(codec_ctx->channel_layout);
codec_ctx->bit_rate = 128000;
codec_ctx->time_base.num = 1;
codec_ctx->time_base.den = codec_ctx->sample_rate;
ret = avcodec_open2(codec_ctx, codec, nullptr);
if (ret < 0)
{
printf("avcodec_open2 error(%s)\n", GetFfmpegERR(ret));
goto END;
}
printf("codec_ctx->frame_size:%d\n", codec_ctx->frame_size);
codec_avframe = av_frame_alloc();
if (!codec_avframe)
{
printf("av_frame_alloc error\n");
goto END;
}
codec_avframe->format = codec_ctx->sample_fmt; // pcm的采样格式
codec_avframe->sample_rate = codec_ctx->sample_rate;
codec_avframe->channel_layout = codec_ctx->channel_layout;
codec_avframe->channels = av_get_channel_layout_nb_channels(codec_avframe->channel_layout);
codec_avframe->nb_samples = codec_ctx->frame_size;
ret = av_frame_get_buffer(codec_avframe, 0);
if (ret < 0)
{
printf("av_frame_get_buffer error(%s)\n", GetFfmpegERR(ret));
goto END;
}
avframe = av_frame_alloc();
if (!avframe)
{
printf("av_frame_alloc error\n");
goto END;
}
avframe->format = AV_SAMPLE_FMT_FLT; // pcm的采样格式
avframe->sample_rate = 44100;
avframe->channel_layout = AV_CH_LAYOUT_STEREO;
avframe->channels = av_get_channel_layout_nb_channels(avframe->channel_layout);
avframe->nb_samples = 1024;
ret = av_samples_get_buffer_size(nullptr,
avframe->channels,
avframe->nb_samples,
(AVSampleFormat)(avframe->format),
1);
if (ret < 0)
{
printf("av_samples_get_buffer_size error(%s)\n", GetFfmpegERR(ret));
goto END;
}
frame_data_bytes = av_get_bytes_per_sample((AVSampleFormat)(avframe->format)) * av_get_channel_layout_nb_channels(avframe->channel_layout) * avframe->nb_samples;
if (frame_data_bytes != ret)
{
printf("frame_data_bytes != ret\n");
goto END;
}
ret = av_frame_get_buffer(avframe, 0);
if (ret < 0)
{
printf("av_frame_get_buffer error(%s)\n", GetFfmpegERR(ret));
goto END;
}
avpacket = av_packet_alloc();
if (!avpacket)
{
printf("av_packet_alloc error\n");
goto END;
}
ret = avformat_alloc_output_context2(&fmt_ctx, nullptr, nullptr, aac_file);
if (ret < 0)
{
printf("avformat_alloc_output_context2 error(%s)\n", GetFfmpegERR(ret));
goto END;
}
out_fmt = fmt_ctx->oformat; // name:adts long_name:ADTS AAC
avstream = avformat_new_stream(fmt_ctx, codec);
if (!avstream)
{
printf("avformat_new_stream error\n");
goto END;
}
ret = avcodec_parameters_from_context(avstream->codecpar, codec_ctx);
if (ret < 0)
{
printf("avcodec_parameters_from_context error(%s)\n", GetFfmpegERR(ret));
goto END;
}
if (!(fmt_ctx->flags & AVFMT_FLAG_NOFILLIN))
{
ret = avio_open(&(fmt_ctx->pb), aac_file, AVIO_FLAG_WRITE);
if (ret < 0)
{
printf("avio_open error(%s)\n", GetFfmpegERR(ret));
goto END;
}
}
in_fp = fopen(pcm_file, "rb");
if (!in_fp)
{
printf("fopen error\n");
goto END;
}
// int av_channel_layout_from_mask(AVChannelLayout *channel_layout, uint64_t mask);
ret = av_channel_layout_from_mask(&src_channel_layout, avframe->channel_layout);
if (ret < 0)
{
printf("av_channel_layout_from_mask error(%s)\n", GetFfmpegERR(ret));
goto END;
}
ret = av_channel_layout_from_mask(&dest_channel_layout, codec_avframe->channel_layout);
if (ret < 0)
{
printf("av_channel_layout_from_mask error(%s)\n", GetFfmpegERR(ret));
goto END;
}
// int swr_alloc_set_opts2(struct SwrContext **ps,
// const AVChannelLayout *out_ch_layout, enum AVSampleFormat out_sample_fmt, int out_sample_rate,
// const AVChannelLayout *in_ch_layout, enum AVSampleFormat in_sample_fmt, int in_sample_rate,
// int log_offset, void *log_ctx);
ret = swr_alloc_set_opts2(&swr_ctx,
&dest_channel_layout, (AVSampleFormat)(codec_avframe->format), codec_avframe->sample_rate,
&src_channel_layout, (AVSampleFormat)(avframe->format), avframe->sample_rate,
0, nullptr);
if (ret < 0)
{
printf("swr_alloc_set_opts2 error(%s)\n", GetFfmpegERR(ret));
goto END;
}
ret = avformat_write_header(fmt_ctx, nullptr);
if (ret < 0)
{
printf("avformat_write_header error(%s)\n", GetFfmpegERR(ret));
goto END;
}
while (1)
{
if (feof(in_fp))
{
printf("feof\n");
break;
}
if (av_sample_fmt_is_planar((AVSampleFormat)(avframe->format)))
{
n = fread(avframe->data[0], sizeof(uint8_t), frame_data_bytes / 2, in_fp);
if ((int)n != frame_data_bytes / 2)
{
printf("n != frame_data_bytes / 2\n");
}
n = fread(avframe->data[1], sizeof(uint8_t), frame_data_bytes / 2, in_fp);
if ((int)n != frame_data_bytes / 2)
{
printf("n != frame_data_bytes / 2\n");
}
}
else
{
n = fread(avframe->data[0], sizeof(uint8_t), frame_data_bytes, in_fp);
if ((int)n != frame_data_bytes)
{
printf("n != frame_data_bytes\n");
}
}
ret = swr_convert_frame(swr_ctx, codec_avframe, avframe);
if (ret < 0)
{
printf("swr_convert_frame error(%s)\n", GetFfmpegERR(ret));
goto END;
}
codec_avframe->pts = pts;
++pts;
ret = avcodec_send_frame(codec_ctx, codec_avframe);
if (ret < 0)
{
if (ret == AVERROR(EAGAIN))
{
printf("read output first\n");
}
else
{
printf("avcodec_send_frame error(%s)\n", GetFfmpegERR(ret));
break;
}
}
while (1)
{
ret = avcodec_receive_packet(codec_ctx, avpacket);
if (ret < 0)
{
if (ret == AVERROR(EAGAIN))
{
printf("send input first\n");
break;
}
else
{
printf("avcodec_receive_packet error(%s)\n", GetFfmpegERR(ret));
break;
}
}
ret = av_write_frame(fmt_ctx, avpacket);
if (ret < 0)
{
printf("av_write_frame error(%s)\n", GetFfmpegERR(ret));
av_packet_unref(avpacket);
goto END;
}
av_packet_unref(avpacket);
}
}
ret = avcodec_send_frame(codec_ctx, nullptr);
while (1)
{
ret = avcodec_receive_packet(codec_ctx, avpacket);
if (ret < 0)
{
if (ret == AVERROR(EAGAIN))
{
printf("send input first\n");
break;
}
else
{
printf("avcodec_receive_packet error(%s)\n", GetFfmpegERR(ret));
break;
}
}
ret = av_write_frame(fmt_ctx, avpacket);
if (ret < 0)
{
printf("av_write_frame error(%s)\n", GetFfmpegERR(ret));
av_packet_unref(avpacket);
goto END;
}
av_packet_unref(avpacket);
}
ret = av_write_trailer(fmt_ctx);
if (ret != 0)
{
printf("av_write_trailer error(%s)\n", GetFfmpegERR(ret));
goto END;
}
END:
if (swr_ctx)
{
swr_free(&swr_ctx);
swr_ctx = nullptr;
}
if (in_fp)
{
fclose(in_fp);
in_fp = nullptr;
}
if (avpacket)
{
av_packet_free(&avpacket);
avpacket = nullptr;
}
if (codec_avframe)
{
av_frame_free(&codec_avframe);
codec_avframe = nullptr;
}
if (avframe)
{
av_frame_free(&avframe);
avframe = nullptr;
}
if (codec_ctx)
{
avcodec_free_context(&codec_ctx);
codec_ctx = nullptr;
}
if (fmt_ctx)
{
if (fmt_ctx->pb)
{
avio_close(fmt_ctx->pb);
fmt_ctx->pb = nullptr;
}
avformat_free_context(fmt_ctx);
fmt_ctx = nullptr;
}
}
performance
