2023-03-01：用moonfdd/ffmpeg-go库，将h264文件编码为mp4文件。
答案2023-03-01：
使用 github.com/moonfdd/ffmpeg-go 库。现在我们有h264的流，创建一个mp4文件，新建一条流并将h264流插入进去。（暂时没有音频部分）。
转换流程图为：
在这里插入图片描述命令如下：
代码语言：shell复制go run ./examples/a13.video_encode_h2642mp4/main.go参考了13：h264编码为mp4，代码用golang编写。代码如下：
代码语言：go复制package main
import (
"fmt"
"os"
"os/exec"
"github.com/moonfdd/ffmpeg-go/ffcommon"
"github.com/moonfdd/ffmpeg-go/libavcodec"
"github.com/moonfdd/ffmpeg-go/libavformat"
"github.com/moonfdd/ffmpeg-go/libavutil"
)
func main() {
os.Setenv("Path", os.Getenv("Path") ";./lib")
ffcommon.SetAvutilPath("./lib/avutil-56.dll")
ffcommon.SetAvcodecPath("./lib/avcodec-58.dll")
ffcommon.SetAvdevicePath("./lib/avdevice-56.dll")
ffcommon.SetAvfilterPath("./lib/avfilter-56.dll")
ffcommon.SetAvformatPath("./lib/avformat-58.dll")
ffcommon.SetAvpostprocPath("./lib/postproc-55.dll")
ffcommon.SetAvswresamplePath("./lib/swresample-3.dll")
ffcommon.SetAvswscalePath("./lib/swscale-5.dll")
genDir := "./out"
_, err := os.Stat(genDir)
if err != nil {
if os.IsNotExist(err) {
os.Mkdir(genDir, 0777) // Everyone can read write and execute
}
}
frame_index := 0 //统计帧数
inVStreamIndex := -1
outVStreamIndex := -1 //输入输出视频流在文件中的索引位置
inVFileName := "./out/result.h264"
outFileName := "./out/result.mp4"
//是否存在h264文件
_, err = os.Stat(inVFileName)
if err != nil {
if os.IsNotExist(err) {
fmt.Println("create h264 file")
exec.Command("./lib/ffmpeg", "-i", "./resources/big_buck_bunny.mp4", "-vcodec", "copy", "-an", inVFileName, "-y").CombinedOutput()
}
}
var inVFmtCtx *libavformat.AVFormatContext
var outFmtCtx *libavformat.AVFormatContext
var codecPara *libavcodec.AVCodecParameters
var outVStream *libavformat.AVStream
var outCodec *libavcodec.AVCodec
var outCodecCtx *libavcodec.AVCodecContext
var outCodecPara *libavcodec.AVCodecParameters
var inVStream *libavformat.AVStream
pkt := libavcodec.AvPacketAlloc()
for {
//======================输入部分============================//
//打开输入文件
if libavformat.AvformatOpenInput(&inVFmtCtx, inVFileName, nil, nil) < 0 {
fmt.Printf("Cannot open input file.n")
break
}
//查找输入文件中的流
if inVFmtCtx.AvformatFindStreamInfo(nil) < 0 {
fmt.Printf("Cannot find stream info in input file.n")
break
}
//查找视频流在文件中的位置
for i := uint32(0); i < inVFmtCtx.NbStreams; i {
if inVFmtCtx.GetStream(i).Codecpar.CodecType == libavutil.AVMEDIA_TYPE_VIDEO {
inVStreamIndex = int(i)
break
}
}
codecPara = inVFmtCtx.GetStream(uint32(inVStreamIndex)).Codecpar //输入视频流的编码参数
fmt.Printf("===============Input information========>n")
inVFmtCtx.AvDumpFormat(0, inVFileName, 0)
fmt.Printf("===============Input information========<n")
//=====================输出部分=========================//
//打开输出文件并填充格式数据
if libavformat.AvformatAllocOutputContext2(&outFmtCtx, nil, "", outFileName) < 0 {
fmt.Printf("Cannot alloc output file context.n")
break
}
//打开输出文件并填充数据
if libavformat.AvioOpen(&outFmtCtx.Pb, outFileName, libavformat.AVIO_FLAG_READ_WRITE) < 0 {
fmt.Printf("output file open failed.n")
break
}
//在输出的mp4文件中创建一条视频流
outVStream = outFmtCtx.AvformatNewStream(nil)
if outVStream == nil {
fmt.Printf("Failed allocating output stream.n")
break
}
outVStream.TimeBase.Den = 25
outVStream.TimeBase.Num = 1
outVStreamIndex = int(outVStream.Index)
//查找编码器
outCodec = libavcodec.AvcodecFindEncoder(codecPara.CodecId)
if outCodec == nil {
fmt.Printf("Cannot find any encoder.n")
break
}
//从输入的h264编码器数据复制一份到输出文件的编码器中
outCodecCtx = outCodec.AvcodecAllocContext3()
outCodecPara = outFmtCtx.GetStream(uint32(outVStream.Index)).Codecpar
if libavcodec.AvcodecParametersCopy(outCodecPara, codecPara) < 0 {
fmt.Printf("Cannot copy codec para.n")
break
}
if outCodecCtx.AvcodecParametersToContext(outCodecPara) < 0 {
fmt.Printf("Cannot alloc codec ctx from para.n")
break
}
outCodecCtx.TimeBase.Den = 25
outCodecCtx.TimeBase.Num = 1
//打开输出文件需要的编码器
if outCodecCtx.AvcodecOpen2(outCodec, nil) < 0 {
fmt.Printf("Cannot open output codec.n")
break
}
fmt.Printf("============Output Information=============>n")
outFmtCtx.AvDumpFormat(0, outFileName, 1)
fmt.Printf("============Output Information=============<n")
//写入文件头
if outFmtCtx.AvformatWriteHeader(nil) < 0 {
fmt.Printf("Cannot write header to file.n")
return
}
//===============编码部分===============//
inVStream = inVFmtCtx.GetStream(uint32(inVStreamIndex))
for inVFmtCtx.AvReadFrame(pkt) >= 0 { //循环读取每一帧直到读完
if pkt.StreamIndex == uint32(inVStreamIndex) { //确保处理的是视频流
//FIXME：No PTS (Example: Raw H.264)
//Simple Write PTS
//如果当前处理帧的显示时间戳为0或者没有等等不是正常值
if pkt.Pts == libavutil.AV_NOPTS_VALUE {
fmt.Printf("frame_index:%dn", frame_index)
//Write PTS
time_base1 := inVStream.TimeBase
//Duration between 2 frames (us)
calc_duration := libavutil.AV_TIME_BASE / libavutil.AvQ2d(inVStream.RFrameRate)
//Parameters
pkt.Pts = int64((float64(frame_index) * calc_duration) / (libavutil.AvQ2d(time_base1) * float64(libavutil.AV_TIME_BASE)))
pkt.Dts = pkt.Pts
pkt.Duration = int64(calc_duration / (libavutil.AvQ2d(time_base1) * float64(libavutil.AV_TIME_BASE)))
frame_index
}
//Convert PTS/DTS
pkt.Pts = libavutil.AvRescaleQRnd(pkt.Pts, inVStream.TimeBase, outVStream.TimeBase, libavutil.AV_ROUND_NEAR_INF|libavutil.AV_ROUND_PASS_MINMAX)
pkt.Dts = libavutil.AvRescaleQRnd(pkt.Dts, inVStream.TimeBase, outVStream.TimeBase, libavutil.AV_ROUND_NEAR_INF|libavutil.AV_ROUND_PASS_MINMAX)
pkt.Duration = libavutil.AvRescaleQ(pkt.Duration, inVStream.TimeBase, outVStream.TimeBase)
pkt.Pos = -1
pkt.StreamIndex = uint32(outVStreamIndex)
fmt.Printf("Write 1 Packet. size:]tpts:%dtduration:%dn", pkt.Size, pkt.Pts, pkt.Duration)
//Write
if outFmtCtx.AvInterleavedWriteFrame(pkt) < 0 {
fmt.Printf("Error muxing packetn")
break
}
pkt.AvPacketUnref()
}
}
outFmtCtx.AvWriteTrailer()
break
}
//===========================释放所有指针===============================//
libavcodec.AvPacketFree(&pkt)
libavformat.AvformatCloseInput(&outFmtCtx)
outCodecCtx.AvcodecClose()
libavcodec.AvcodecFreeContext(&outCodecCtx)
libavformat.AvformatCloseInput(&inVFmtCtx)
inVFmtCtx.AvformatFreeContext()
// outFmtCtx.Pb.AvioClose()//案例里面有，但个人感觉不对
fmt.Println("-----------------------------------------")
_, err = exec.Command("./lib/ffplay.exe", "./out/result.mp4").Output()
if err != nil {
fmt.Println("play err = ", err)
}
}
在这里插入图片描述
