MP4 Created Using FFmpeg API Can't Be Played in Media Players - c++

Question

I've been struggling with this issue for days. There are similar issues posted here and around the web, but none of the solutions seem to work for me. They are possibly outdated?
Here is the current iteration of code I'm using to generate the MP4 file.
It generates a simple 2 second .mp4 file that fails to play in any player I've tried. If I run that mp4 file back through the FFmpeg command line, it will generate a perfectly playable movie out of it. So the data is there.
Also, if you modify the output file name in this code from .mp4 to .avi, this code generates a playable avi file too. So whatever it is, it is tied to the H.264 format.
I'm sure I'm missing something simple, but for the life of me, I can't figure out what that is.
Any help would be greatly appreciated!
Here is a link to the VC++ project. MovieMaker.zip
MovieMaker.h
#pragma once
extern "C"
{
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libswscale/swscale.h>
#include <libavutil/opt.h>
}
class FMovieMaker
{
public:
~FMovieMaker();
bool Initialize(const char* FileName, int Width = 1920, int Height = 1080, int FPS = 30, int BitRate = 2000);
bool RecordFrame(uint8_t* BGRAData);
bool Finalize();
bool IsInitialized() const { return bInitialized; }
int GetWidth() const { return CodecContext ? CodecContext->width : 0; }
int GetHeight() const { return CodecContext ? CodecContext->height : 0; }
private:
bool EncodeFrame(bool bFinalize);
void Log(const char* fmt, ...);
AVOutputFormat* OutputFormat = nullptr;
AVFormatContext* FormatContext = nullptr;
AVCodecContext* CodecContext = nullptr;
AVFrame* Frame = nullptr;
SwsContext* ColorConverter = nullptr;
int64_t RecordedFrames = 0;
bool bInitialized = false;
};
MovieMaker.cpp
#include "MovieMaker.h"
FMovieMaker::~FMovieMaker()
{
if (IsInitialized())
Finalize();
}
bool FMovieMaker::Initialize(const char* FileName, int Width /*= 1920*/, int Height /*= 1080*/, int FPS /*= 30*/, int BitRate /*= 2000*/)
{
OutputFormat = av_guess_format(nullptr, FileName, nullptr);
if (!OutputFormat)
{
Log("Couldn't guess the output format from the filename: %s", FileName);
return false;
}
AVCodecID CodecID = OutputFormat->video_codec;
if (CodecID == AV_CODEC_ID_NONE)
{
Log("Could not determine a codec to use");
return false;
}
/* allocate the output media context */
int ErrorCode = avformat_alloc_output_context2(&FormatContext, OutputFormat, nullptr, FileName);
if (ErrorCode < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Failed to allocate format context: %s", Error);
return false;
}
else if (!FormatContext)
{
Log("Failed to get format from filename: %s", FileName);
return false;
}
/* find the video encoder */
const AVCodec* Codec = avcodec_find_encoder(CodecID);
if (!Codec)
{
Log("Codec '%d' not found", CodecID);
return false;
}
/* create the video stream */
AVStream* Stream = avformat_new_stream(FormatContext, Codec);
if (!Stream)
{
Log("Failed to allocate stream");
return false;
}
/* create the codec context */
CodecContext = avcodec_alloc_context3(Codec);
if (!CodecContext)
{
Log("Could not allocate video codec context");
return false;
}
Stream->codecpar->codec_id = OutputFormat->video_codec;
Stream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
Stream->codecpar->width = Width;
Stream->codecpar->height = Height;
Stream->codecpar->format = AV_PIX_FMT_YUV420P;
Stream->codecpar->bit_rate = (int64_t)BitRate * 1000;
avcodec_parameters_to_context(CodecContext, Stream->codecpar);
CodecContext->time_base = { 1, FPS };
CodecContext->max_b_frames = 2;
CodecContext->gop_size = 12;
CodecContext->framerate = { FPS, 1 };
if (Stream->codecpar->codec_id == AV_CODEC_ID_H264)
av_opt_set(CodecContext, "preset", "medium", 0);
else if (Stream->codecpar->codec_id == AV_CODEC_ID_H265)
av_opt_set(CodecContext, "preset", "medium", 0);
avcodec_parameters_from_context(Stream->codecpar, CodecContext);
if (FormatContext->oformat->flags & AVFMT_GLOBALHEADER)
CodecContext->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
if ((ErrorCode = avcodec_open2(CodecContext, Codec, NULL)) < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Failed to open codec: %s", Error);
return false;
}
if (!(OutputFormat->flags & AVFMT_NOFILE))
{
if ((ErrorCode = avio_open(&FormatContext->pb, FileName, AVIO_FLAG_WRITE)) < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Failed to open file: %s", Error);
return false;
}
}
Stream->time_base = CodecContext->time_base;
if ((ErrorCode = avformat_write_header(FormatContext, NULL)) < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Failed to write header: %s", Error);
return false;
}
CodecContext->time_base = Stream->time_base;
av_dump_format(FormatContext, 0, FileName, 1);
// create the frame
{
Frame = av_frame_alloc();
if (!Frame)
{
Log("Could not allocate video frame");
return false;
}
Frame->format = CodecContext->pix_fmt;
Frame->width = CodecContext->width;
Frame->height = CodecContext->height;
ErrorCode = av_frame_get_buffer(Frame, 32);
if (ErrorCode < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Could not allocate the video frame data: %s", Error);
return false;
}
}
// create a color converter
{
ColorConverter = sws_getContext(CodecContext->width, CodecContext->height, AV_PIX_FMT_BGRA,
CodecContext->width, CodecContext->height, AV_PIX_FMT_YUV420P, 0, 0, 0, 0);
if (!ColorConverter)
{
Log("Could not allocate color converter");
return false;
}
}
bInitialized = true;
return true;
}
bool FMovieMaker::RecordFrame(uint8_t* BGRAData)
{
if (!bInitialized)
{
Log("Cannot record frames on an uninitialized Video Recorder");
return false;
}
/*make sure the frame data is writable */
int ErrorCode = av_frame_make_writable(Frame);
if (ErrorCode < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Could not make the frame writable: %s", Error);
return false;
}
/* convert the bgra bitmap data into yuv frame data */
int inLinesize[1] = { 4 * CodecContext->width }; // RGB stride
sws_scale(ColorConverter, &BGRAData, inLinesize, 0, CodecContext->height, Frame->data, Frame->linesize);
//Frame->pts = RecordedFrames++;
Frame->pts = CodecContext->time_base.den / CodecContext->time_base.num * CodecContext->framerate.den / CodecContext->framerate.num * (RecordedFrames++);
//The following assumes that codecContext->time_base = (AVRational){1, 1};
//Frame->pts = frameduration * (RecordedFrames++) * Stream->time_base.den / (Stream->time_base.num * fps);
//Frame->pts += av_rescale_q(1, CodecContext->time_base, Stream->time_base);
return EncodeFrame(false);
}
bool FMovieMaker::EncodeFrame(bool bFinalize)
{
/* send the frame to the encoder */
int ErrorCode = avcodec_send_frame(CodecContext, bFinalize ? nullptr : Frame);
if (ErrorCode < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Error sending a frame for encoding: %s", Error);
return false;
}
AVPacket Packet;
av_init_packet(&Packet);
Packet.data = NULL;
Packet.size = 0;
Packet.flags |= AV_PKT_FLAG_KEY;
Packet.pts = Frame->pts;
if (avcodec_receive_packet(CodecContext, &Packet) == 0)
{
//std::cout << "pkt key: " << (Packet.flags & AV_PKT_FLAG_KEY) << " " << Packet.size << " " << (counter++) << std::endl;
uint8_t* size = ((uint8_t*)Packet.data);
//std::cout << "first: " << (int)size[0] << " " << (int)size[1] << " " << (int)size[2] << " " << (int)size[3] << " " << (int)size[4] << " " << (int)size[5] << " " << (int)size[6] << " " << (int)size[7] << std::endl;
av_interleaved_write_frame(FormatContext, &Packet);
av_packet_unref(&Packet);
}
return true;
}
bool FMovieMaker::Finalize()
{
if (!bInitialized)
{
Log("Cannot finalize uninitialized Video Recorder");
return false;
}
//DELAYED FRAMES
AVPacket Packet;
av_init_packet(&Packet);
Packet.data = NULL;
Packet.size = 0;
for (;;)
{
avcodec_send_frame(CodecContext, NULL);
if (avcodec_receive_packet(CodecContext, &Packet) == 0)
{
av_interleaved_write_frame(FormatContext, &Packet);
av_packet_unref(&Packet);
}
else
break;
}
av_write_trailer(FormatContext);
if (!(OutputFormat->flags & AVFMT_NOFILE))
{
int ErrorCode = avio_close(FormatContext->pb);
if (ErrorCode < 0)
{
char Error[AV_ERROR_MAX_STRING_SIZE];
av_make_error_string(Error, AV_ERROR_MAX_STRING_SIZE, ErrorCode);
Log("Failed to close file: %s", Error);
}
}
if (Frame)
{
av_frame_free(&Frame);
Frame = nullptr;
}
if (CodecContext)
{
avcodec_free_context(&CodecContext);
CodecContext = nullptr;
}
if (FormatContext)
{
avformat_free_context(FormatContext);
FormatContext = nullptr;
}
if (ColorConverter)
{
sws_freeContext(ColorConverter);
ColorConverter = nullptr;
}
bInitialized = false;
return true;
}
void FMovieMaker::Log(const char* fmt, ...)
{
va_list args;
fprintf(stderr, "LOG: ");
va_start(args, fmt);
vfprintf(stderr, fmt, args);
va_end(args);
fprintf(stderr, "\n");
}
Main.cpp
#include "MovieMaker.h"
uint8_t FtoB(float x)
{
if (x <= 0.0f)
return 0;
if (x >= 1.0f)
return 255;
else
return (uint8_t)(x * 255.0f);
}
void SetPixelColor(float X, float Y, float Width, float Height, float t, uint8_t* BGRA)
{
t += 12.0f; // more interesting colors at this time
float P[2] = { 0.1f * X - 25.0f, 0.1f * Y - 25.0f };
float V = sqrtf(P[0] * P[0] + P[1] * P[1]);
BGRA[0] = FtoB(sinf(V + t / 0.78f));
BGRA[1] = FtoB(sinf(V + t / 10.0f));
BGRA[2] = FtoB(sinf(V + t / 36e2f));
BGRA[3] = 255;
}
int main()
{
FMovieMaker MovieMaker;
const char* FileName = "C:\\ffmpeg\\MyMovieMakerMovie.mp4";
int Width = 640;
int Height = 480;
int FPS = 30;
int BitRateKBS = 2000;
if (MovieMaker.Initialize(FileName, Width, Height, FPS, BitRateKBS))
{
int Size = Width * 4 * Height;
uint8_t* BGRAData = new uint8_t[Size];
memset(BGRAData, 255, Size);
for (float Frame = 0; Frame < 60; Frame++)
{
// fill the image data with something interesting
for (float Y = 0; Y < Height; Y++)
{
for (float X = 0; X < Width; X++)
{
SetPixelColor(X, Y, (float)Width, (float)Height, Frame / (float)FPS, &BGRAData[(int)(Y * Width + X) * 4]);
}
}
if (!MovieMaker.RecordFrame(BGRAData))
break;
}
delete[] BGRAData;
MovieMaker.Finalize();
}
}
If I have the lines that add the AV_CODEC_FLAG_GLOBAL_HEADER flag like shown above, I get all sorts of issues in the output from ffprobe MyMovieMakerMovie.mp4.
C:\ffmpeg>ffprobe MyMovieMakerMovie.mp4
ffprobe version 4.2.2 Copyright (c) 2007-2019 the FFmpeg developers
built with gcc 9.2.1 (GCC) 20200122
configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
libavutil 56. 31.100 / 56. 31.100
libavcodec 58. 54.100 / 58. 54.100
libavformat 58. 29.100 / 58. 29.100
libavdevice 58. 8.100 / 58. 8.100
libavfilter 7. 57.100 / 7. 57.100
libswscale 5. 5.100 / 5. 5.100
libswresample 3. 5.100 / 3. 5.100
libpostproc 55. 5.100 / 55. 5.100
[h264 # 000001d44b795b00] non-existing PPS 0 referenced
[h264 # 000001d44b795b00] decode_slice_header error
[h264 # 000001d44b795b00] no frame!
...
[h264 # 000001d44b795b00] non-existing PPS 0 referenced
[h264 # 000001d44b795b00] decode_slice_header error
[h264 # 000001d44b795b00] no frame!
[mov,mp4,m4a,3gp,3g2,mj2 # 000001d44b783880] decoding for stream 0 failed
[mov,mp4,m4a,3gp,3g2,mj2 # 000001d44b783880] Could not find codec parameters for stream 0 (Video: h264 (avc1 / 0x31637661), none, 640x480, 20528 kb/s): unspecified pixel format
Consider increasing the value for the 'analyzeduration' and 'probesize' options
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'MyMovieMakerMovie.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.29.100
Duration: 00:00:01.97, start: 0.000000, bitrate: 20529 kb/s
Stream #0:0(und): Video: h264 (avc1 / 0x31637661), none, 640x480, 20528 kb/s, 30.51 fps, 30 tbr, 15360 tbn, 30720 tbc (default)
Metadata:
handler_name : VideoHandler
Without adding the AV_CODEC_FLAG_GLOBAL_HEADER flag, I get a clean output from ffprobe, but the video still doesn't play. Notice it thinks the frame rate is 30.51, I'm not sure why.
C:\ffmpeg>ffprobe MyMovieMakerMovie.mp4
ffprobe version 4.2.2 Copyright (c) 2007-2019 the FFmpeg developers
built with gcc 9.2.1 (GCC) 20200122
configuration: --disable-static --enable-shared --enable-gpl --enable-version3 --enable-sdl2 --enable-fontconfig --enable-gnutls --enable-iconv --enable-libass --enable-libdav1d --enable-libbluray --enable-libfreetype --enable-libmp3lame --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libopenjpeg --enable-libopus --enable-libshine --enable-libsnappy --enable-libsoxr --enable-libtheora --enable-libtwolame --enable-libvpx --enable-libwavpack --enable-libwebp --enable-libx264 --enable-libx265 --enable-libxml2 --enable-libzimg --enable-lzma --enable-zlib --enable-gmp --enable-libvidstab --enable-libvorbis --enable-libvo-amrwbenc --enable-libmysofa --enable-libspeex --enable-libxvid --enable-libaom --enable-libmfx --enable-amf --enable-ffnvcodec --enable-cuvid --enable-d3d11va --enable-nvenc --enable-nvdec --enable-dxva2 --enable-avisynth --enable-libopenmpt
libavutil 56. 31.100 / 56. 31.100
libavcodec 58. 54.100 / 58. 54.100
libavformat 58. 29.100 / 58. 29.100
libavdevice 58. 8.100 / 58. 8.100
libavfilter 7. 57.100 / 7. 57.100
libswscale 5. 5.100 / 5. 5.100
libswresample 3. 5.100 / 3. 5.100
libpostproc 55. 5.100 / 55. 5.100
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'MyMovieMakerMovie.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf58.29.100
Duration: 00:00:01.97, start: 0.000000, bitrate: 20530 kb/s
Stream #0:0(und): Video: h264 (High) (avc1 / 0x31637661), yuv420p, 640x480, 20528 kb/s, 30.51 fps, 30 tbr, 15360 tbn, 60 tbc (default)
Metadata:
handler_name : VideoHandler