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// license:BSD-3-Clause
// copyright-holders:Aaron Giles
/***************************************************************************

    ldverify.c

    Laserdisc AVI/CHD verifier.

****************************************************************************/

#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <new>
#include <cassert>
#include "coretmpl.h"
#include "aviio.h"
#include "avhuff.h"
#include "bitmap.h"
#include "chd.h"
#include "vbiparse.h"



//**************************************************************************
//  CONSTANTS
//**************************************************************************

const int REPORT_BLANKS_THRESHOLD = 50;



//**************************************************************************
//  TYPE DEFINITIONS
//**************************************************************************

struct movie_info
{
	double  framerate;
	int     numframes;
	int     width;
	int     height;
	int     samplerate;
	int     channels;
};

struct video_info
{
	int first_whitefield;
	bool saw_leadin;
	bool saw_leadout;
	int last_frame;
	int last_chapter;
	int cadence;
	uint32_t cadence_history;
	int prev_whitefield;
	int min_overall;
	int max_overall;
	int first_blank_frame;
	int first_blank_field;
	int num_blank_fields;
	int first_low_frame;
	int first_low_field;
	int num_low_fields;
	int first_high_frame;
	int first_high_field;
	int num_high_fields;
};

struct audio_info
{
	int min_lsample;
	int min_rsample;
	int max_lsample;
	int max_rsample;
	int min_lsample_count;
	int min_rsample_count;
	int max_lsample_count;
	int max_rsample_count;
	int sample_count;
};



//**************************************************************************
//  GLOBAL VARIABLES
//**************************************************************************

static bool chdinterlaced;



//**************************************************************************
//  AVI HANDLING
//**************************************************************************

//-------------------------------------------------
//  open_avi - open an AVI file and return
//  information about it
//-------------------------------------------------

static void *open_avi(const char *filename, movie_info &info)
{
	// open the file
	avi_file::ptr avi;
	avi_file::error avierr = avi_file::open(filename, avi);
	if (avierr != avi_file::error::NONE)
	{
		fprintf(stderr, "Error opening AVI file: %s\n", avi_file::error_string(avierr));
		return nullptr;
	}

	// extract movie info
	const avi_file::movie_info &aviinfo = avi->get_movie_info();
	info.framerate = (double)aviinfo.video_timescale / (double)aviinfo.video_sampletime;
	info.numframes = aviinfo.video_numsamples;
	info.width = aviinfo.video_width;
	info.height = aviinfo.video_height;
	info.samplerate = aviinfo.audio_samplerate;
	info.channels = aviinfo.audio_channels;
	return avi.release();
}


//-------------------------------------------------
//  read_avi - read a frame from an AVI file
//-------------------------------------------------

static bool read_avi(void *file, int frame, bitmap_yuy16 &bitmap, int16_t *lsound, int16_t *rsound, int &samples)
{
	avi_file *avifile = reinterpret_cast<avi_file *>(file);

	// read the frame
	avi_file::error avierr = avifile->read_video_frame(frame, bitmap);
	if (avierr != avi_file::error::NONE)
		return false;

	// read the samples
	const avi_file::movie_info &aviinfo = avifile->get_movie_info();
	uint32_t firstsample = (uint64_t(aviinfo.audio_samplerate) * uint64_t(frame) * uint64_t(aviinfo.video_sampletime) + aviinfo.video_timescale - 1) / uint64_t(aviinfo.video_timescale);
	uint32_t lastsample = (uint64_t(aviinfo.audio_samplerate) * uint64_t(frame + 1) * uint64_t(aviinfo.video_sampletime) + aviinfo.video_timescale - 1) / uint64_t(aviinfo.video_timescale);
	avierr = avifile->read_sound_samples(0, firstsample, lastsample - firstsample, lsound);
	avierr = avifile->read_sound_samples(1, firstsample, lastsample - firstsample, rsound);
	if (avierr != avi_file::error::NONE)
		return false;
	samples = lastsample - firstsample;
	return true;
}


//-------------------------------------------------
//  close_avi - close an AVI file
//-------------------------------------------------

static void close_avi(void *file)
{
	avi_file *avifile = reinterpret_cast<avi_file *>(file);
	delete avifile;
}



//**************************************************************************
//  CHD HANDLING
//**************************************************************************

//-------------------------------------------------
//  open_chd - open a CHD file and return
//  information about it
//-------------------------------------------------

static void *open_chd(const char *filename, movie_info &info)
{
	auto chd = new chd_file;

	// open the file
	chd_error chderr = chd->open(filename);
	if (chderr != CHDERR_NONE)
	{
		fprintf(stderr, "Error opening CHD file: %s\n", chd_file::error_string(chderr));
		delete chd;
		return nullptr;
	}

	// get the metadata
	std::string metadata;
	chderr = chd->read_metadata(AV_METADATA_TAG, 0, metadata);
	if (chderr != CHDERR_NONE)
	{
		fprintf(stderr, "Error getting A/V metadata: %s\n", chd_file::error_string(chderr));
		delete chd;
		return nullptr;
	}

	// extract the info
	int fps, fpsfrac, width, height, interlaced, channels, rate;
	if (sscanf(metadata.c_str(), AV_METADATA_FORMAT, &fps, &fpsfrac, &width, &height, &interlaced, &channels, &rate) != 7)
	{
		fprintf(stderr, "Improperly formatted metadata\n");
		delete chd;
		return nullptr;
	}

	// extract movie info
	info.framerate = (fps * 1000000 + fpsfrac) / 1000000.0;
	info.numframes = chd->hunk_count();
	info.width = width;
	info.height = height;
	info.samplerate = rate;
	info.channels = channels;

	// convert to an interlaced frame
	chdinterlaced = interlaced;
	if (interlaced)
	{
		info.framerate /= 2;
		info.numframes = (info.numframes + 1) / 2;
		info.height *= 2;
	}
	return chd;
}


//-------------------------------------------------
//  read_chd - read a frame from a CHD file
//-------------------------------------------------

static int read_chd(void *file, int frame, bitmap_yuy16 &bitmap, int16_t *lsound, int16_t *rsound, int &samples)
{
	chd_file *chdfile = reinterpret_cast<chd_file *>(file);

	// loop over fields
	int interlace_factor = chdinterlaced ? 2 : 1;
	samples = 0;
	for (int fieldnum = 0; fieldnum < interlace_factor; fieldnum++)
	{
		// make a fake bitmap for this field
		avhuff_decompress_config avconfig;
		avconfig.video.wrap(&bitmap.pix16(fieldnum), bitmap.width(), bitmap.height() / interlace_factor, bitmap.rowpixels() * interlace_factor);

		// configure the codec
		uint32_t numsamples;
		avconfig.maxsamples = 48000;
		avconfig.actsamples = &numsamples;
		avconfig.audio[0] = &lsound[samples];
		avconfig.audio[1] = &rsound[samples];

		// configure the decompressor for this frame
		chdfile->codec_configure(CHD_CODEC_AVHUFF, AVHUFF_CODEC_DECOMPRESS_CONFIG, &avconfig);

		// read the frame
		chd_error chderr = chdfile->read_hunk(frame * interlace_factor + fieldnum, nullptr);
		if (chderr != CHDERR_NONE)
			return false;

		// account for samples read
		samples += numsamples;
	}
	return true;
}


//-------------------------------------------------
//  close_chd - close a CHD file
//-------------------------------------------------

static void close_chd(void *file)
{
	chd_file *chdfile = reinterpret_cast<chd_file *>(file);
	delete chdfile;
}



//**************************************************************************
//  CORE IMPLEMENTATION
//**************************************************************************

//-------------------------------------------------
//  init_video - init video info structure
//-------------------------------------------------

static void init_video(video_info &video)
{
	video.first_whitefield = -1;
	video.saw_leadin = false;
	video.saw_leadout = false;
	video.last_frame = -1;
	video.last_chapter = -1;
	video.cadence = -1;
	video.cadence_history = 0;
	video.prev_whitefield = -1;
	video.min_overall = 255;
	video.max_overall = 0;
	video.first_blank_frame = -1;
	video.first_blank_field = -1;
	video.num_blank_fields = -1;
	video.first_low_frame = -1;
	video.first_low_field = -1;
	video.num_low_fields = -1;
	video.first_high_frame = -1;
	video.first_high_field = -1;
	video.num_high_fields = -1;
}


//-------------------------------------------------
//  verify_video - verify video frame
//-------------------------------------------------

static void verify_video(video_info &video, int frame, bitmap_yuy16 &bitmap)
{
	// loop over fields
	const int fields_per_frame = 2;
	for (int fieldnum = 0; fieldnum < fields_per_frame; fieldnum++)
	{
		// output status
		if (frame % 10 == 0 && fieldnum == 0)
			fprintf(stderr, "%6d.%d...\r", frame, fieldnum);

		// parse the VBI data
		vbi_metadata metadata;
		vbi_parse_all(&bitmap.pix16(fieldnum), bitmap.rowpixels() * 2, bitmap.width(), 8, &metadata);

		// if we have data in both 17 and 18, it should match
		if (metadata.line17 != 0 && metadata.line18 != 0 && metadata.line17 != metadata.line18)
		{
			printf("%6d.%d: line 17 and 18 data does not match (17=%06X 18=%06X) (WARNING)\n", frame, fieldnum, metadata.line17, metadata.line18);
			printf("%6d.%d: selected %06X based on bit confidence\n", frame, fieldnum, metadata.line1718);
		}

		// is this a lead-in code?
		if (metadata.line1718 == VBI_CODE_LEADIN)
		{
			// if we haven't seen lead-in yet, detect it
			if (!video.saw_leadin)
			{
				video.saw_leadin = true;
				printf("%6d.%d: lead-in code detected\n", frame, fieldnum);
			}

			// if we've previously seen chapters/frames, that's weird
			if (video.last_frame != -1 || video.last_chapter != -1)
				printf("%6d.%d: lead-in code detected after frame/chapter data (WARNING)\n", frame, fieldnum);
		}

		// is this a lead-out code?
		if (metadata.line1718 == VBI_CODE_LEADOUT)
		{
			// if we haven't seen lead-in yet, detect it
			if (!video.saw_leadout)
			{
				video.saw_leadout = true;
				printf("%6d.%d: lead-out code detected\n", frame, fieldnum);
				if (video.last_frame != -1)
					printf("%6d.%d: final frame number was %d\n", frame, fieldnum, video.last_frame);
				else
					printf("%6d.%d: never detected any frame numbers (ERROR)\n", frame, fieldnum);
			}

			// if we've previously seen chapters/frames, that's weird
			if (video.last_frame == -1)
				printf("%6d.%d: lead-out code detected with no frames detected beforehand (WARNING)\n", frame, fieldnum);
		}

		// is this a frame code?
		if ((metadata.line1718 & VBI_MASK_CAV_PICTURE) == VBI_CODE_CAV_PICTURE)
		{
			int framenum = VBI_CAV_PICTURE(metadata.line1718);

			// did we see any leadin?
			if (!video.saw_leadin)
			{
				printf("%6d.%d: detected frame number but never saw any lead-in (WARNING)\n", frame, fieldnum);
				video.saw_leadin = true;
			}

			// if this is the first frame, make sure it's 1
			if (video.last_frame == -1)
			{
				if (framenum == 0)
					printf("%6d.%d: detected frame 0\n", frame, fieldnum);
				else if (framenum == 1)
					printf("%6d.%d: detected frame 1\n", frame, fieldnum);
				else
					printf("%6d.%d: first frame number is not 0 or 1 (%d) (ERROR)\n", frame, fieldnum, framenum);
			}

			// print an update every 10000 frames
			if (framenum != 0 && framenum % 10000 == 0)
				printf("%6d.%d: detected frame %d\n", frame, fieldnum, framenum);

			// if this frame is not consecutive, it's an error
			if (video.last_frame != -1 && framenum != video.last_frame + 1)
				printf("%6d.%d: gap in frame number sequence (%d->%d) (ERROR)\n", frame, fieldnum, video.last_frame, framenum);

			// remember the frame number
			video.last_frame = framenum;

			// if we've seen a white flag before, but it's not here, warn
			if (video.first_whitefield != -1 && !metadata.white)
				printf("%6d.%d: detected frame number but no white flag (WARNING)\n", frame, fieldnum);
		}

		// is the whiteflag set?
		int field = frame * fields_per_frame + fieldnum;
		if (metadata.white)
		{
			// if this is the first white flag we see, count it
			if (video.first_whitefield == -1)
			{
				video.first_whitefield = field;
				printf("%6d.%d: first white flag seen\n", frame, fieldnum);
			}

			// if we've seen frame numbers before, but not here, warn
			if (video.last_frame != -1 && (metadata.line1718 & VBI_MASK_CAV_PICTURE) != VBI_CODE_CAV_PICTURE)
				printf("%6d.%d: detected white flag but no frame number (WARNING)\n", frame, fieldnum);
		}

		// if this is the start of a frame, handle cadence
		if (metadata.white || (metadata.line1718 & VBI_MASK_CAV_PICTURE) == VBI_CODE_CAV_PICTURE)
		{
			// if we've seen frames, but we're not yet to the lead-out, check the cadence
			if (video.last_frame != -1 && !video.saw_leadout)
			{
				// make sure we have a proper history
				if (video.prev_whitefield != -1)
					video.cadence_history = (video.cadence_history << 4) | ((field - video.prev_whitefield) & 0x0f);
				video.prev_whitefield = field;

				// if we don't know our cadence yet, determine it
				if (video.cadence == -1 && (video.cadence_history & 0xf00) != 0)
				{
					if ((video.cadence_history & 0xfff) == 0x222)
					{
						printf("%6d.%d: detected 2:2 cadence\n", frame, fieldnum);
						video.cadence = 4;
					}
					else if ((video.cadence_history & 0xfff) == 0x323)
					{
						printf("%6d.%d: detected 3:2 cadence\n", frame, fieldnum);
						video.cadence = 5;
					}
					else if ((video.cadence_history & 0xfff) == 0x232)
					{
						printf("%6d.%d: detected 2:3 cadence\n", frame, fieldnum);
						video.cadence = 5;
					}
					else
					{
						printf("%6d.%d: unknown cadence (history %d:%d:%d) (WARNING)\n", frame, fieldnum,
								(video.cadence_history >> 8) & 15, (video.cadence_history >> 4) & 15, video.cadence_history & 15);
					}
				}

				// if we know our cadence, make sure we stick to it
				if (video.cadence != -1)
				{
					if (video.cadence == 4 && (video.cadence_history & 0xfff) != 0x222)
					{
						printf("%6d.%d: missed cadence (history %d:%d:%d) (WARNING)\n", frame, fieldnum,
								(video.cadence_history >> 8) & 15, (video.cadence_history >> 4) & 15, video.cadence_history & 15);
						video.cadence = -1;
						video.cadence_history = 0;
					}
					else if (video.cadence == 5 && (video.cadence_history & 0xfff) != 0x323 && (video.cadence_history & 0xfff) != 0x232)
					{
						printf("%6d.%d: missed cadence (history %d:%d:%d) (WARNING)\n", frame, fieldnum,
								(video.cadence_history >> 8) & 15, (video.cadence_history >> 4) & 15, video.cadence_history & 15);
						video.cadence = -1;
						video.cadence_history = 0;
					}
				}
			}
		}

		// now examine the active video signal
		uint32_t yhisto[256] = { 0 };
		uint32_t crhisto[256] = { 0 };
		uint32_t cbhisto[256] = { 0 };
		int pixels = 0;
		for (int y = 22*2 + fieldnum; y < bitmap.height(); y += 2)
		{
			for (int x = 16; x < 720 - 16; x++)
			{
				yhisto[bitmap.pix16(y, x) >> 8]++;
				if (x % 2 == 0)
					cbhisto[bitmap.pix16(y, x) & 0xff]++;
				else
					crhisto[bitmap.pix16(y, x) & 0xff]++;
			}
			pixels += 720 - 16 - 16;
		}

		// remove the top/bottom 0.1% of Y
		int remaining = pixels / 1000;
		int yminval;
		for (yminval = 0; (remaining -= yhisto[yminval]) >= 0; yminval++) ;
		remaining = pixels / 1000;
		int ymaxval;
		for (ymaxval = 255; (remaining -= yhisto[ymaxval]) >= 0; ymaxval--) ;

		// remove the top/bottom 0.1% of Cb
		remaining = pixels / 500;
		int cbminval;
		for (cbminval = 0; (remaining -= cbhisto[cbminval]) >= 0; cbminval++) ;
		remaining = pixels / 500;
		int cbmaxval;
		for (cbmaxval = 255; (remaining -= cbhisto[cbmaxval]) >= 0; cbmaxval--) ;

		// remove the top/bottom 0.1% of Cr
		remaining = pixels / 500;
		int crminval;
		for (crminval = 0; (remaining -= crhisto[crminval]) >= 0; crminval++) ;
		remaining = pixels / 500;
		int crmaxval;
		for (crmaxval = 255; (remaining -= crhisto[crmaxval]) >= 0; crmaxval--) ;

		// track blank frames
		if (ymaxval - yminval < 10 && cbmaxval - cbminval < 10 && crmaxval - cbmaxval < 10)
		{
			if (video.first_blank_frame == -1)
			{
				video.first_blank_frame = frame;
				video.first_blank_field = fieldnum;
				video.num_blank_fields = 0;
			}
			video.num_blank_fields++;
		}
		else if (video.num_blank_fields > 0)
		{
			if (video.num_blank_fields >= REPORT_BLANKS_THRESHOLD)
				printf("%6d.%d-%6d.%d: blank frames for %d fields (INFO)\n", video.first_blank_frame, video.first_blank_field, frame, fieldnum, video.num_blank_fields);
			video.first_blank_frame = video.first_blank_field = video.num_blank_fields = -1;
		}

		// update the overall min/max
		video.min_overall = std::min(yminval, video.min_overall);
		video.max_overall = std::max(ymaxval, video.max_overall);

		// track low fields
		if (yminval <= 0)
		{
			if (video.first_low_frame == -1)
			{
				video.first_low_frame = frame;
				video.first_low_field = fieldnum;
				video.num_low_fields = 0;
			}
			video.num_low_fields++;
		}
		else if (video.num_low_fields > 0)
		{
			printf("%6d.%d-%6d.%d: active video signal level low for %d fields (WARNING)\n", video.first_low_frame, video.first_low_field, frame, fieldnum, video.num_low_fields);
			video.first_low_frame = video.first_low_field = video.num_low_fields = -1;
		}

		// track high fields
		if (ymaxval >= 255)
		{
			if (video.first_high_frame == -1)
			{
				video.first_high_frame = frame;
				video.first_high_field = fieldnum;
				video.num_high_fields = 0;
			}
			video.num_high_fields++;
		}
		else if (video.num_high_fields > 0)
		{
			printf("%6d.%d-%6d.%d: active video signal level high for %d fields (WARNING)\n", video.first_high_frame, video.first_high_field, frame, fieldnum, video.num_high_fields);
			video.first_high_frame = video.first_high_field = video.num_high_fields = -1;
		}
	}
}


//-------------------------------------------------
//  verify_video_final - final verification
//-------------------------------------------------

static void verify_video_final(video_info &video, int frame, bitmap_yuy16 &bitmap)
{
	int fields_per_frame = (bitmap.height() >= 288) ? 2 : 1;
	int field = frame * fields_per_frame;

	// did we ever see any white flags?
	if (video.first_whitefield == -1)
		printf("Track %6d.%d: never saw any white flags (WARNING)\n", field / fields_per_frame, 0);

	// did we ever see any lead-out?
	if (!video.saw_leadout)
		printf("Track %6d.%d: never saw any lead-out (WARNING)\n", field / fields_per_frame, 0);

	// any remaining high/low reports?
	if (video.num_blank_fields >= REPORT_BLANKS_THRESHOLD)
		printf("%6d.%d-%6d.%d: blank frames for %d fields (INFO)\n", video.first_blank_frame, video.first_blank_field, frame, 0, video.num_blank_fields);
	if (video.num_low_fields > 0)
		printf("%6d.%d-%6d.%d: active video signal level low for %d fields (WARNING)\n", video.first_low_frame, video.first_low_field, frame, 0, video.num_low_fields);
	if (video.num_high_fields > 0)
		printf("%6d.%d-%6d.%d: active video signal level high for %d fields (WARNING)\n", video.first_high_frame, video.first_high_field, frame, 0, video.num_high_fields);

	// summary info
	printf("\nVideo summary:\n");
	printf("  Overall video range: %d-%d (%02X-%02X)\n", video.min_overall, video.max_overall, video.min_overall, video.max_overall);
}


//-------------------------------------------------
//  init_audio - init audio info structure
//-------------------------------------------------

static void init_audio(audio_info &audio)
{
	audio.min_lsample = 32767;
	audio.min_rsample = 32767;
	audio.max_lsample = -32768;
	audio.max_rsample = -32768;
	audio.min_lsample_count = 0;
	audio.min_rsample_count = 0;
	audio.max_lsample_count = 0;
	audio.max_rsample_count = 0;
	audio.sample_count = 0;
}


//-------------------------------------------------
//  verify_audio - verify audio data
//-------------------------------------------------

static void verify_audio(audio_info &audio, const int16_t *lsound, const int16_t *rsound, int samples)
{
	// count the overall samples
	audio.sample_count += samples;

	// iterate over samples, tracking min/max
	for (int sampnum = 0; sampnum < samples; sampnum++)
	{
		// did we hit a minimum on the left?
		if (lsound[sampnum] < audio.min_lsample)
		{
			audio.min_lsample = lsound[sampnum];
			audio.min_lsample_count = 1;
		}
		else if (lsound[sampnum] == audio.min_lsample)
			audio.min_lsample_count++;

		// did we hit a maximum on the left?
		if (lsound[sampnum] > audio.max_lsample)
		{
			audio.max_lsample = lsound[sampnum];
			audio.max_lsample_count = 1;
		}
		else if (lsound[sampnum] == audio.max_lsample)
			audio.max_lsample_count++;

		// did we hit a minimum on the right?
		if (rsound[sampnum] < audio.min_rsample)
		{
			audio.min_rsample = rsound[sampnum];
			audio.min_rsample_count = 1;
		}
		else if (rsound[sampnum] == audio.min_rsample)
			audio.min_rsample_count++;

		// did we hit a maximum on the right?
		if (rsound[sampnum] > audio.max_rsample)
		{
			audio.max_rsample = rsound[sampnum];
			audio.max_rsample_count = 1;
		}
		else if (rsound[sampnum] == audio.max_rsample)
			audio.max_rsample_count++;
	}
}


//-------------------------------------------------
//  verify_audio_final - final verification
//-------------------------------------------------

static void verify_audio_final(audio_info &audio)
{
	printf("\nAudio summary:\n");
	printf("  Overall channel 0 range: %d-%d (%04X-%04X)\n", audio.min_lsample, audio.max_lsample, uint16_t(audio.min_lsample), uint16_t(audio.max_lsample));
	printf("  Overall channel 1 range: %d-%d (%04X-%04X)\n", audio.min_rsample, audio.max_rsample, uint16_t(audio.min_rsample), uint16_t(audio.max_rsample));
}


//-------------------------------------------------
//  usage - display program usage
//-------------------------------------------------

static int usage(void)
{
	fprintf(stderr, "Usage: \n");
	fprintf(stderr, "  ldverify <avifile.avi|chdfile.chd>\n");
	return 1;
}


//-------------------------------------------------
//  main - main entry point
//-------------------------------------------------

int main(int argc, char *argv[])
{
	try
	{
		// init globals
		audio_info audio;
		init_audio(audio);
		video_info video;
		init_video(video);

		// verify arguments
		if (argc < 2)
			return usage();
		const char *srcfile = argv[1];

		// check extension of file
		int srcfilelen = strlen(srcfile);
		if (srcfilelen < 4)
			return usage();
		bool isavi;
		if (tolower((uint8_t)srcfile[srcfilelen-3]) == 'a' && tolower((uint8_t)srcfile[srcfilelen-2]) == 'v' && tolower((uint8_t)srcfile[srcfilelen-1]) == 'i')
			isavi = true;
		else if (tolower((uint8_t)srcfile[srcfilelen-3]) == 'c' && tolower((uint8_t)srcfile[srcfilelen-2]) == 'h' && tolower((uint8_t)srcfile[srcfilelen-1]) == 'd')
			isavi = false;
		else
			return usage();

		// open the file
		printf("Processing file: %s\n", srcfile);
		movie_info info = { 0 };
		void *file = isavi ? open_avi(srcfile, info) : open_chd(srcfile, info);
		if (file == nullptr)
		{
			fprintf(stderr, "Unable to open file '%s'\n", srcfile);
			return 1;
		}

		// comment on the video dimensions
		printf("Video dimensions: %dx%d\n", info.width, info.height);
		if (info.width != 720)
			printf("WARNING: Unexpected video width (should be 720)\n");
		if (info.height != 524)
			printf("WARNING: Unexpected video height (should be 262 or 524)\n");

		// comment on the video frame rate
		printf("Video frame rate: %.2fHz\n", info.framerate);
		if (int(info.framerate * 100.0 + 0.5) != 2997)
			printf("WARNING: Unexpected frame rate (should be 29.97Hz)\n");

		// comment on the sample rate
		printf("Sample rate: %dHz\n", info.samplerate);
		if (info.samplerate != 48000)
			printf("WARNING: Unexpected sampele rate (should be 48000Hz)\n");

		// allocate a bitmap
		bitmap_yuy16 bitmap(info.width, info.height);

		// allocate sound buffers
		std::vector<int16_t> lsound(info.samplerate);
		std::vector<int16_t> rsound(info.samplerate);

		// loop over frames
		int frame = 0;
		int samples = 0;
		while (isavi ? read_avi(file, frame, bitmap, &lsound[0], &rsound[0], samples) : read_chd(file, frame, bitmap, &lsound[0], &rsound[0], samples))
		{
			verify_video(video, frame, bitmap);
			verify_audio(audio, &lsound[0], &rsound[0], samples);
			frame++;
		}

		// close the files
		isavi ? close_avi(file) : close_chd(file);

		// final output
		verify_video_final(video, frame, bitmap);
		verify_audio_final(audio);
	}
	catch (std::bad_alloc &)
	{
		fprintf(stderr, "Out of memory allocating memory\n");
		return 1;
	}

	return 0;
}