hedgewars/avwrapper/avwrapper.c
author koda
Sun, 20 Mar 2016 03:08:51 -0400
changeset 11617 b7d5d75469ee
parent 11548 3617c611406b
child 11619 3c959df6638e
permissions -rw-r--r--
Move pixel format conversion from uVideoRec to AVWrapper This has several benefits, being in C-land allows us to better use libav API and avoid mixing memory allocated from Pascal. Also the C code for the conversion loop generated by GCC or Clang is probably more optimized than by Freepascal. Finally it will simplify code in the future if we are going to enable any other pixel format than yuv420p. Change the coefficients to improve color accuracy during conversion.

/*
 * Hedgewars, a free turn based strategy game
 * Copyright (c) 2004-2015 Andrey Korotaev <unC0Rr@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdarg.h>

#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libavutil/avutil.h"
#include "libavutil/mathematics.h"

#if (defined _MSC_VER)
#define AVWRAP_DECL __declspec(dllexport)
#elif ((__GNUC__ >= 3) && (!__EMX__) && (!sun))
#define AVWRAP_DECL __attribute__((visibility("default")))
#else
#define AVWRAP_DECL
#endif

static AVFormatContext* g_pContainer;
static AVOutputFormat* g_pFormat;
static AVStream* g_pAStream;
static AVStream* g_pVStream;
static AVFrame* g_pAFrame;
static AVFrame* g_pVFrame;
static AVCodec* g_pACodec;
static AVCodec* g_pVCodec;
static AVCodecContext* g_pAudio;
static AVCodecContext* g_pVideo;

static int g_Width, g_Height;
static uint32_t g_Frequency, g_Channels;
static int g_VQuality;
static AVRational g_Framerate;

static FILE* g_pSoundFile;
static int16_t* g_pSamples;
static int g_NumSamples;


// compatibility section
#if LIBAVCODEC_VERSION_MAJOR < 54
#define OUTBUFFER_SIZE 200000
static uint8_t g_OutBuffer[OUTBUFFER_SIZE];
#define avcodec_open2(x, y, z)              avcodec_open(x, y)
#endif

#if LIBAVCODEC_VERSION_MAJOR < 56
#define av_frame_alloc                      avcodec_alloc_frame
#define av_frame_free                       av_freep
#define av_packet_rescale_ts                rescale_ts

static void rescale_ts(AVPacket *pkt, AVRational ctb, AVRational stb)
{
    if (pkt->pts != AV_NOPTS_VALUE)
        pkt->pts = av_rescale_q(pkt->pts, ctb, stb);
    if (pkt->dts != AV_NOPTS_VALUE)
        pkt->dts = av_rescale_q(pkt->dts, ctb, stb);
    if (pkt->duration > 0)
        pkt->duration = av_rescale_q(pkt->duration, ctb, stb);
}
#endif

#ifndef AV_CODEC_CAP_DELAY
#define AV_CODEC_CAP_DELAY                  CODEC_CAP_DELAY
#endif
#ifndef AV_CODEC_CAP_VARIABLE_FRAME_SIZE
#define AV_CODEC_CAP_VARIABLE_FRAME_SIZE    CODEC_CAP_VARIABLE_FRAME_SIZE
#endif
#ifndef AV_CODEC_FLAG_GLOBAL_HEADER
#define AV_CODEC_FLAG_GLOBAL_HEADER         CODEC_FLAG_GLOBAL_HEADER
#endif
#ifndef AV_CODEC_FLAG_QSCALE
#define AV_CODEC_FLAG_QSCALE                CODEC_FLAG_QSCALE
#endif

#if LIBAVFORMAT_VERSION_MAJOR < 53
#define AVIO_FLAG_WRITE                     AVIO_WRONLY
#endif

#if LIBAVFORMAT_VERSION_MAJOR < 54
#define avformat_new_stream(x, y)           av_new_stream(x, y->type == AVMEDIA_TYPE_AUDIO)
#endif

#if LIBAVUTIL_VERSION_MAJOR < 54
#define AV_PIX_FMT_YUV420P                  PIX_FMT_YUV420P
#endif


// pointer to function from hwengine (uUtils.pas)
static void (*AddFileLogRaw)(const char* pString);

static int FatalError(const char* pFmt, ...)
{
    char Buffer[1024];
    va_list VaArgs;

    va_start(VaArgs, pFmt);
    vsnprintf(Buffer, 1024, pFmt, VaArgs);
    va_end(VaArgs);

    AddFileLogRaw("Error in av-wrapper: ");
    AddFileLogRaw(Buffer);
    AddFileLogRaw("\n");
    return(-1);
}

// Function to be called from libav for logging.
// Note: libav can call LogCallback from different threads
// (there is mutex in AddFileLogRaw).
static void LogCallback(void* p, int Level, const char* pFmt, va_list VaArgs)
{
    char Buffer[1024];

    vsnprintf(Buffer, 1024, pFmt, VaArgs);
    AddFileLogRaw(Buffer);
}

static void Log(const char* pFmt, ...)
{
    char Buffer[1024];
    va_list VaArgs;

    va_start(VaArgs, pFmt);
    vsnprintf(Buffer, 1024, pFmt, VaArgs);
    va_end(VaArgs);

    AddFileLogRaw(Buffer);
}

static void AddAudioStream()
{
    g_pAStream = avformat_new_stream(g_pContainer, g_pACodec);
    if(!g_pAStream)
    {
        Log("Could not allocate audio stream\n");
        return;
    }
    g_pAStream->id = 1;

    g_pAudio = g_pAStream->codec;

    avcodec_get_context_defaults3(g_pAudio, g_pACodec);
    g_pAudio->codec_id = g_pACodec->id;

    // put parameters
    g_pAudio->sample_fmt = AV_SAMPLE_FMT_S16;
    g_pAudio->sample_rate = g_Frequency;
    g_pAudio->channels = g_Channels;

    // set time base as invers of sample rate
    g_pAudio->time_base.den = g_pAStream->time_base.den = g_Frequency;
    g_pAudio->time_base.num = g_pAStream->time_base.num = 1;

    // set quality
    g_pAudio->bit_rate = 160000;

    // for codecs that support variable bitrate use it, it should be better
    g_pAudio->flags |= AV_CODEC_FLAG_QSCALE;
    g_pAudio->global_quality = 1*FF_QP2LAMBDA;

    // some formats want stream headers to be separate
    if (g_pFormat->flags & AVFMT_GLOBALHEADER)
        g_pAudio->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;

    // open it
    if (avcodec_open2(g_pAudio, g_pACodec, NULL) < 0)
    {
        Log("Could not open audio codec %s\n", g_pACodec->long_name);
        return;
    }

#if LIBAVCODEC_VERSION_MAJOR >= 54
    if (g_pACodec->capabilities & AV_CODEC_CAP_VARIABLE_FRAME_SIZE)
#else
    if (g_pAudio->frame_size == 0)
#endif
        g_NumSamples = 4096;
    else
        g_NumSamples = g_pAudio->frame_size;
    g_pSamples = (int16_t*)av_malloc(g_NumSamples*g_Channels*sizeof(int16_t));
    g_pAFrame = av_frame_alloc();
    if (!g_pAFrame)
    {
        Log("Could not allocate frame\n");
        return;
    }
}

// returns non-zero if there is more sound, -1 in case of error
static int WriteAudioFrame()
{
    if (!g_pAStream)
        return 0;

    AVPacket Packet;
    av_init_packet(&Packet);
    Packet.data = NULL;
    Packet.size = 0;

    int NumSamples = fread(g_pSamples, 2*g_Channels, g_NumSamples, g_pSoundFile);

#if LIBAVCODEC_VERSION_MAJOR >= 53
    AVFrame* pFrame = NULL;
    if (NumSamples > 0)
    {
        g_pAFrame->nb_samples = NumSamples;
        avcodec_fill_audio_frame(g_pAFrame, g_Channels, AV_SAMPLE_FMT_S16,
                                 (uint8_t*)g_pSamples, NumSamples*2*g_Channels, 1);
        pFrame = g_pAFrame;
    }
    // when NumSamples == 0 we still need to call encode_audio2 to flush
    int got_packet;
    if (avcodec_encode_audio2(g_pAudio, &Packet, pFrame, &got_packet) != 0)
        return FatalError("avcodec_encode_audio2 failed");
    if (!got_packet)
        return 0;

    av_packet_rescale_ts(&Packet, g_pAudio->time_base, g_pAStream->time_base);
#else
    if (NumSamples == 0)
        return 0;
    int BufferSize = OUTBUFFER_SIZE;
    if (g_pAudio->frame_size == 0)
        BufferSize = NumSamples*g_Channels*2;
    Packet.size = avcodec_encode_audio(g_pAudio, g_OutBuffer, BufferSize, g_pSamples);
    if (Packet.size == 0)
        return 1;
    if (g_pAudio->coded_frame && g_pAudio->coded_frame->pts != AV_NOPTS_VALUE)
        Packet.pts = av_rescale_q(g_pAudio->coded_frame->pts, g_pAudio->time_base, g_pAStream->time_base);
    Packet.flags |= AV_PKT_FLAG_KEY;
    Packet.data = g_OutBuffer;
#endif

    // Write the compressed frame to the media file.
    Packet.stream_index = g_pAStream->index;
    if (av_interleaved_write_frame(g_pContainer, &Packet) != 0)
        return FatalError("Error while writing audio frame");
    return 1;
}

// add a video output stream
static int AddVideoStream()
{
    g_pVStream = avformat_new_stream(g_pContainer, g_pVCodec);
    if (!g_pVStream)
        return FatalError("Could not allocate video stream");

    g_pVideo = g_pVStream->codec;

    avcodec_get_context_defaults3(g_pVideo, g_pVCodec);
    g_pVideo->codec_id = g_pVCodec->id;

    // put parameters
    // resolution must be a multiple of two
    g_pVideo->width  = g_Width  & ~1; // make even (dimensions should be even)
    g_pVideo->height = g_Height & ~1; // make even
    /* time base: this is the fundamental unit of time (in seconds) in terms
       of which frame timestamps are represented. for fixed-fps content,
       timebase should be 1/framerate and timestamp increments should be
       identically 1. */
    g_pVideo->time_base.den = g_pVStream->time_base.den = g_Framerate.num;
    g_pVideo->time_base.num = g_pVStream->time_base.num = g_Framerate.den;

    g_pVideo->pix_fmt = AV_PIX_FMT_YUV420P;

    // set quality
    if (g_VQuality > 100)
        g_pVideo->bit_rate = g_VQuality;
    else
    {
        g_pVideo->flags |= AV_CODEC_FLAG_QSCALE;
        g_pVideo->global_quality = g_VQuality*FF_QP2LAMBDA;
    }

    // some formats want stream headers to be separate
    if (g_pFormat->flags & AVFMT_GLOBALHEADER)
        g_pVideo->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;

#if LIBAVCODEC_VERSION_MAJOR < 53
    // for some versions of ffmpeg x264 options must be set explicitly
    if (strcmp(g_pVCodec->name, "libx264") == 0)
    {
        g_pVideo->coder_type = FF_CODER_TYPE_AC;
        g_pVideo->flags |= CODEC_FLAG_LOOP_FILTER;
        g_pVideo->crf = 23;
        g_pVideo->thread_count = 3;
        g_pVideo->me_cmp = FF_CMP_CHROMA;
        g_pVideo->partitions = X264_PART_I8X8 | X264_PART_I4X4 | X264_PART_P8X8 | X264_PART_B8X8;
        g_pVideo->me_method = ME_HEX;
        g_pVideo->me_subpel_quality = 7;
        g_pVideo->me_range = 16;
        g_pVideo->gop_size = 250;
        g_pVideo->keyint_min = 25;
        g_pVideo->scenechange_threshold = 40;
        g_pVideo->i_quant_factor = 0.71;
        g_pVideo->b_frame_strategy = 1;
        g_pVideo->qcompress = 0.6;
        g_pVideo->qmin = 10;
        g_pVideo->qmax = 51;
        g_pVideo->max_qdiff = 4;
        g_pVideo->max_b_frames = 3;
        g_pVideo->refs = 3;
        g_pVideo->directpred = 1;
        g_pVideo->trellis = 1;
        g_pVideo->flags2 = CODEC_FLAG2_BPYRAMID | CODEC_FLAG2_MIXED_REFS | CODEC_FLAG2_WPRED | CODEC_FLAG2_8X8DCT | CODEC_FLAG2_FASTPSKIP;
        g_pVideo->weighted_p_pred = 2;
    }
#endif

    // open the codec
    if (avcodec_open2(g_pVideo, g_pVCodec, NULL) < 0)
        return FatalError("Could not open video codec %s", g_pVCodec->long_name);

    g_pVFrame = av_frame_alloc();
    if (!g_pVFrame)
        return FatalError("Could not allocate frame");
    av_frame_unref(g_pVFrame);

    g_pVFrame->width = g_Width;
    g_pVFrame->height = g_Height;
    g_pVFrame->format = AV_PIX_FMT_YUV420P;

    return avcodec_default_get_buffer2(g_pVideo, g_pVFrame, 0);
}

static int WriteFrame(AVFrame* pFrame)
{
    double AudioTime, VideoTime;
    int ret;
    // write interleaved audio frame
    if (g_pAStream)
    {
        VideoTime = (double)g_pVFrame->pts * g_pVStream->time_base.num/g_pVStream->time_base.den;
        do
        {
            AudioTime = (double)g_pAFrame->pts * g_pAStream->time_base.num/g_pAStream->time_base.den;
            ret = WriteAudioFrame();
        }
        while (AudioTime < VideoTime && ret);
        if (ret < 0)
            return ret;
    }

    if (!g_pVStream)
        return 0;

    AVPacket Packet;
    av_init_packet(&Packet);
    Packet.data = NULL;
    Packet.size = 0;

    g_pVFrame->pts++;
#if LIBAVCODEC_VERSION_MAJOR < 58
    if (g_pFormat->flags & AVFMT_RAWPICTURE)
    {
        /* raw video case. The API will change slightly in the near
           future for that. */
        Packet.flags |= AV_PKT_FLAG_KEY;
        Packet.stream_index = g_pVStream->index;
        Packet.data = (uint8_t*)pFrame;
        Packet.size = sizeof(AVPicture);

        if (av_interleaved_write_frame(g_pContainer, &Packet) != 0)
            return FatalError("Error while writing video frame");
        return 0;
    }
    else
#endif
    {
#if LIBAVCODEC_VERSION_MAJOR >= 54
        int got_packet;
        if (avcodec_encode_video2(g_pVideo, &Packet, pFrame, &got_packet) < 0)
            return FatalError("avcodec_encode_video2 failed");
        if (!got_packet)
            return 0;

        av_packet_rescale_ts(&Packet, g_pVideo->time_base, g_pVStream->time_base);
#else
        Packet.size = avcodec_encode_video(g_pVideo, g_OutBuffer, OUTBUFFER_SIZE, pFrame);
        if (Packet.size < 0)
            return FatalError("avcodec_encode_video failed");
        if (Packet.size == 0)
            return 0;

        if( g_pVideo->coded_frame->pts != AV_NOPTS_VALUE)
            Packet.pts = av_rescale_q(g_pVideo->coded_frame->pts, g_pVideo->time_base, g_pVStream->time_base);
        if( g_pVideo->coded_frame->key_frame )
            Packet.flags |= AV_PKT_FLAG_KEY;
        Packet.data = g_OutBuffer;
#endif
        // write the compressed frame in the media file
        Packet.stream_index = g_pVStream->index;
        if (av_interleaved_write_frame(g_pContainer, &Packet) != 0)
            return FatalError("Error while writing video frame");

        return 1;
    }
}

AVWRAP_DECL int AVWrapper_WriteFrame(uint8_t *buf)
{
    int x, y, stride = g_Width * 4;
    uint8_t *data[3];

    // copy pointers, prepare source
    memcpy(data, g_pVFrame->data, sizeof(data));
    buf += (g_Height - 1) * stride;

    // convert to YUV 4:2:0
    for (y = 0; y < g_Height; y++) {
        for (x = 0; x < g_Width; x++) {
            int r = buf[x * 4 + 0];
            int g = buf[x * 4 + 1];
            int b = buf[x * 4 + 2];

            int luma = (int)(0.299f * r +  0.587f * g + 0.114f * b);
            data[0][x] = av_clip_uint8(luma);

            if (!(x & 1) && !(y & 1)) {
                int r = (buf[x * 4 + 0]          + buf[(x + 1) * 4 + 0] +
                         buf[x * 4 + 0 + stride] + buf[(x + 1) * 4 + 0 + stride]) / 4;
                int g = (buf[x * 4 + 1]          + buf[(x + 1) * 4 + 1] +
                         buf[x * 4 + 1 + stride] + buf[(x + 1) * 4 + 1 + stride]) / 4;
                int b = (buf[x * 4 + 2]          + buf[(x + 1) * 4 + 2] +
                         buf[x * 4 + 2 + stride] + buf[(x + 1) * 4 + 2 + stride]) / 4;

                int cr = (int)(-0.14713f * r - 0.28886f * g + 0.436f   * b);
                int cb = (int)( 0.615f   * r - 0.51499f * g - 0.10001f * b);
                data[1][x / 2] = av_clip_uint8(128 + cr);
                data[2][x / 2] = av_clip_uint8(128 + cb);
            }
        }
        buf += -stride;
        data[0] += g_pVFrame->linesize[0];
        if (y & 1) {
            data[1] += g_pVFrame->linesize[1];
            data[2] += g_pVFrame->linesize[2];
        }
    }

    return WriteFrame(g_pVFrame);
}

AVWRAP_DECL int AVWrapper_Init(
         void (*pAddFileLogRaw)(const char*),
         const char* pFilename,
         const char* pDesc,
         const char* pSoundFile,
         const char* pFormatName,
         const char* pVCodecName,
         const char* pACodecName,
         int Width, int Height,
         int FramerateNum, int FramerateDen,
         int VQuality)
{
    int ret;
    AddFileLogRaw = pAddFileLogRaw;
    av_log_set_callback( &LogCallback );

    g_Width  = Width;
    g_Height = Height;
    g_Framerate.num = FramerateNum;
    g_Framerate.den = FramerateDen;
    g_VQuality = VQuality;

    // initialize libav and register all codecs and formats
    av_register_all();

    // find format
    g_pFormat = av_guess_format(pFormatName, NULL, NULL);
    if (!g_pFormat)
        return FatalError("Format \"%s\" was not found", pFormatName);

    // allocate the output media context
    g_pContainer = avformat_alloc_context();
    if (!g_pContainer)
        return FatalError("Could not allocate output context");

    g_pContainer->oformat = g_pFormat;

    // store description of file
    av_dict_set(&g_pContainer->metadata, "comment", pDesc, 0);

    // append extesnion to filename
    char ext[16];
    strncpy(ext, g_pFormat->extensions, 16);
    ext[15] = 0;
    ext[strcspn(ext,",")] = 0;
    snprintf(g_pContainer->filename, sizeof(g_pContainer->filename), "%s.%s", pFilename, ext);

    // find codecs
    g_pVCodec = avcodec_find_encoder_by_name(pVCodecName);
    g_pACodec = avcodec_find_encoder_by_name(pACodecName);

    // add audio and video stream to container
    g_pVStream = NULL;
    g_pAStream = NULL;

    if (g_pVCodec)
    {
        ret = AddVideoStream();
        if (ret < 0)
            return ret;
    }
    else
        Log("Video codec \"%s\" was not found; video will be ignored.\n", pVCodecName);

    if (g_pACodec)
    {
        g_pSoundFile = fopen(pSoundFile, "rb");
        if (g_pSoundFile)
        {
            fread(&g_Frequency, 4, 1, g_pSoundFile);
            fread(&g_Channels, 4, 1, g_pSoundFile);
            AddAudioStream();
        }
        else
            Log("Could not open %s\n", pSoundFile);
    }
    else
        Log("Audio codec \"%s\" was not found; audio will be ignored.\n", pACodecName);

    if (!g_pAStream && !g_pVStream)
        return FatalError("No video, no audio, aborting...");

    // write format info to log
    av_dump_format(g_pContainer, 0, g_pContainer->filename, 1);

    // open the output file, if needed
    if (!(g_pFormat->flags & AVFMT_NOFILE))
    {
        if (avio_open(&g_pContainer->pb, g_pContainer->filename, AVIO_FLAG_WRITE) < 0)
            return FatalError("Could not open output file (%s)", g_pContainer->filename);
    }

    g_pVFrame->pts = -1;

    // write the stream header, if any
    return avformat_write_header(g_pContainer, NULL);
}

AVWRAP_DECL int AVWrapper_Close()
{
    int ret;
    // output buffered frames
    if (g_pVCodec->capabilities & AV_CODEC_CAP_DELAY)
    {
        do
            ret = WriteFrame(NULL);
        while (ret > 0);
        if (ret < 0)
            return ret;
    }
    // output any remaining audio
    do
    {
        ret = WriteAudioFrame();
    }
    while(ret > 0);
    if (ret < 0)
        return ret;

    // write the trailer, if any.
    av_write_trailer(g_pContainer);

    // close the output file
    if (!(g_pFormat->flags & AVFMT_NOFILE))
        avio_close(g_pContainer->pb);

    // free everything
    if (g_pVStream)
    {
        avcodec_close(g_pVideo);
        av_free(g_pVideo);
        av_free(g_pVStream);
        av_frame_free(&g_pVFrame);
    }
    if (g_pAStream)
    {
        avcodec_close(g_pAudio);
        av_free(g_pAudio);
        av_free(g_pAStream);
        av_frame_free(&g_pAFrame);
        av_free(g_pSamples);
        fclose(g_pSoundFile);
    }

    av_free(g_pContainer);
    return 0;
}