avicapture.cpp

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// avicapture.cpp
//
// Copyright (C) 2001, Chris Laurel <claurel@shatters.net>
//
// 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; either version 2
// of the License, or (at your option) any later version.

#include <cmath>

#include "../celengine/gl.h"
#include "../celengine/glext.h"

#include <windowsx.h>
#include <celutil/debug.h>
#include "avicapture.h"

using namespace std;


AVICapture::AVICapture() :
    width(-1),
    height(-1),
    frameRate(30.0f),
    frameCounter(0),
    capturing(false),
    aviFile(NULL),
    aviStream(NULL),
    compAviStream(NULL),
    image(NULL)
{
    AVIFileInit();
}


AVICapture::~AVICapture()
{
    cleanup();
    AVIFileExit();
}


bool AVICapture::start(const string& filename,
                       int w, int h,
                       float fps)
{
    if (capturing)
        return false;

    width = w;
    height = h;
    frameRate = fps;

    if (HIWORD(VideoForWindowsVersion()) < 0x010a)
    {
        // We need to be running on version 1.1 or later
        return false;
    }

    // Compute the width of a row in bytes; pad so that rows are aligned on
    // 4 byte boundaries.
    int rowBytes = (width * 3 + 3) & ~0x3;
    image = new unsigned char[rowBytes * height]; 

    HRESULT hr = AVIFileOpen(&aviFile,
                             filename.c_str(),
                             OF_WRITE | OF_CREATE,
                             NULL);
    if (hr != AVIERR_OK)
    {
        DPRINTF(0, "Erroring creating avi file for capture.\n");
        return false;
    }

    AVISTREAMINFO info;
    ZeroMemory(&info, sizeof info);
    info.fccType = streamtypeVIDEO;
    info.fccHandler = 0;
    info.dwScale = 1;
    info.dwRate = (DWORD) floor(frameRate + 0.5f);
    info.dwSuggestedBufferSize = rowBytes * height;
    SetRect(&info.rcFrame, 0, 0, width, height);
    hr = AVIFileCreateStream(aviFile, &aviStream, &info);
    if (hr != AVIERR_OK)
    {
        DPRINTF(0, "Error %08x creating AVI stream.\n", hr);
        cleanup();
        return false;
    }

    // Display a dialog to allow the user to select compression options
    AVICOMPRESSOPTIONS options;
    AVICOMPRESSOPTIONS* arrOptions[1] = { &options };
    ZeroMemory(&options, sizeof options);

    if (!AVISaveOptions(NULL, 0, 1, &aviStream, 
                        (LPAVICOMPRESSOPTIONS*) &arrOptions))
    {
        // The user either clicked on cancel or there was an error
        cleanup();
        return false;
    }

    hr = AVIMakeCompressedStream(&compAviStream, aviStream, &options, NULL);
    if (hr != AVIERR_OK)
    {
        DPRINTF(0, "Error %08x creating compressed AVI stream.\n", hr);
        cleanup();
        return false;
    }

    BITMAPINFOHEADER bi;
    ZeroMemory(&bi, sizeof bi);
    bi.biSize = sizeof bi;
    bi.biWidth = width;
    bi.biHeight = height;
    bi.biPlanes = 1;
    bi.biBitCount = 24;
    bi.biCompression = BI_RGB;
    bi.biSizeImage = rowBytes * height;
    bi.biXPelsPerMeter = 0;
    bi.biYPelsPerMeter = 0;
    bi.biClrUsed = 0;
    bi.biClrImportant = 0;

    hr = AVIStreamSetFormat(compAviStream, 0, &bi, sizeof bi);
    if (hr != AVIERR_OK)
    {
        DPRINTF(0, "AVIStreamSetFormat failed: %08x\n", hr);
        cleanup();
        return false;
    }

    capturing = true;
    frameCounter = 0;

    return true;
}


bool AVICapture::end()
{
    capturing = false;
    cleanup();

    return true;
}


bool AVICapture::captureFrame()
{
    if (!capturing)
        return false;

    // Get the dimensions of the current viewport
    int viewport[4];
    glGetIntegerv(GL_VIEWPORT, viewport);

    int x = viewport[0] + (viewport[2] - width) / 2;
    int y = viewport[1] + (viewport[3] - height) / 2;
    glReadPixels(x, y, width, height,
                 GL_BGR_EXT, GL_UNSIGNED_BYTE,
                 image);

    int rowBytes = (width * 3 + 3) & ~0x3;

    LONG samplesWritten = 0;
    LONG bytesWritten = 0;
    HRESULT hr = AVIStreamWrite(compAviStream,
                                frameCounter,
                                1,
                                image,
                                rowBytes * height,
                                AVIIF_KEYFRAME,
                                &samplesWritten,
                                &bytesWritten);
    if (hr != AVIERR_OK)
    {
        DPRINTF(0, "AVIStreamWrite failed on frame %d\n", frameCounter);
        return false;
    }

    // printf("Writing frame: %d  %d => %d bytes\n",
    //        frameCounter, rowBytes * height, bytesWritten);
    frameCounter++;

    return true;
}


void AVICapture::cleanup()
{
    if (aviStream != NULL)
    {
        AVIStreamRelease(aviStream);
        aviStream = NULL;
    }
    if (compAviStream != NULL)
    {
        AVIStreamRelease(compAviStream);
        compAviStream = NULL;
    }
    if (aviFile != NULL)
    {
        AVIFileRelease(aviFile);
        aviFile = NULL;
    }
    if (image != NULL)
    {
        delete[] image;
        image = NULL;
    }
}


int AVICapture::getWidth() const
{
    return width;
}

int AVICapture::getHeight() const
{
    return height;
}

float AVICapture::getFrameRate() const
{
    return frameRate;
}

int AVICapture::getFrameCount() const
{
    return frameCounter;
}

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