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/*
 * Copyright (C) 2005 Rik Snel <rsnel@cube.dyndns.org>, license GPL v2
 * - based on vd_lavc.c by A'rpi (C) 2002-2003 
 * - parts from ffmpeg Copyright (c) 2000-2003 Fabrice Bellard
 *
 * This files includes a straightforward (to be) optimized JPEG encoder for
 * the YUV422 format, based on mjpeg code from ffmpeg.
 *
 * For an excellent introduction to the JPEG format, see:
 * http://www.ece.purdue.edu/~bouman/grad-labs/lab8/pdf/lab.pdf
 */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>

#include "config.h"
#include "mp_msg.h"

#include "img_format.h"
#include "mp_image.h"
#include "vf.h"

#ifdef USE_FASTMEMCPY
#include "libvo/fastmemcpy.h"
#endif

/* We need this #define because we need ../libavcodec/common.h to #define 
 * be2me_32, otherwise the linker will complain that it doesn't exist */
#define HAVE_AV_CONFIG_H
#include "libavcodec/avcodec.h"
#include "libavcodec/dsputil.h"
#include "libavcodec/mpegvideo.h"

#undef malloc
#undef free
#undef realloc


/* some convenient #define's, is this portable enough? */
#define VERBOSE(...) mp_msg(MSGT_DECVIDEO, MSGL_V, "vf_zrmjpeg: " __VA_ARGS__)
#define ERROR(...) mp_msg(MSGT_DECVIDEO, MSGL_ERR, "vf_zrmjpeg: " __VA_ARGS__)
#define WARNING(...) mp_msg(MSGT_DECVIDEO, MSGL_WARN, \
		"vf_zrmjpeg: " __VA_ARGS__)


extern int avcodec_inited;

/* zrmjpeg_encode_mb needs access to these tables for the black & white 
 * option */
typedef struct MJpegContext {
	uint8_t huff_size_dc_luminance[12];
	uint16_t huff_code_dc_luminance[12];
	uint8_t huff_size_dc_chrominance[12];
	uint16_t huff_code_dc_chrominance[12];

	uint8_t huff_size_ac_luminance[256];
	uint16_t huff_code_ac_luminance[256];
	uint8_t huff_size_ac_chrominance[256];
	uint16_t huff_code_ac_chrominance[256];
} MJpegContext;

/* Begin excessive code duplication ************************************/
/* Code coming from mpegvideo.c and mjpeg.c in ../libavcodec ***********/

static const unsigned short aanscales[64] = {
	/* precomputed values scaled up by 14 bits */
	16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,
	22725, 31521, 29692, 26722, 22725, 17855, 12299,  6270,
	21407, 29692, 27969, 25172, 21407, 16819, 11585,  5906,
	19266, 26722, 25172, 22654, 19266, 15137, 10426,  5315,
	16384, 22725, 21407, 19266, 16384, 12873,  8867,  4520,
	12873, 17855, 16819, 15137, 12873, 10114,  6967,  3552,
	8867,  12299, 11585, 10426,  8867,  6967,  4799,  2446,
	4520,   6270,  5906,  5315,  4520,  3552,  2446,  1247
};

static void convert_matrix(MpegEncContext *s, int (*qmat)[64], 
		uint16_t (*qmat16)[2][64], const uint16_t *quant_matrix,
		int bias, int qmin, int qmax) {
	int qscale; 

	for(qscale = qmin; qscale <= qmax; qscale++) {
        	int i;
		if (s->dsp.fdct == ff_jpeg_fdct_islow) {
			for (i = 0; i < 64; i++) {
				const int j = s->dsp.idct_permutation[i];
/* 16 <= qscale * quant_matrix[i] <= 7905 
 * 19952         <= aanscales[i] * qscale * quant_matrix[i]      <= 249205026 
 * (1<<36)/19952 >= (1<<36)/(aanscales[i] * qscale * quant_matrix[i]) 
 *                                                       >= (1<<36)/249205026
 * 3444240       >= (1<<36)/(aanscales[i] * qscale * quant_matrix[i])  >= 275 */
				qmat[qscale][i] = (int)((UINT64_C(1) << 
					(QMAT_SHIFT-3))/
					(qscale*quant_matrix[j]));
			}
		} else if (s->dsp.fdct == fdct_ifast) {
            		for (i = 0; i < 64; i++) {
                		const int j = s->dsp.idct_permutation[i];
/* 16 <= qscale * quant_matrix[i] <= 7905 
 * 19952         <= aanscales[i] * qscale * quant_matrix[i]      <= 249205026 
 * (1<<36)/19952 >= (1<<36)/(aanscales[i] * qscale * quant_matrix[i]) 
 *                                                       >= (1<<36)/249205026
 * 3444240       >= (1<<36)/(aanscales[i] * qscale * quant_matrix[i])  >= 275 */
                		qmat[qscale][i] = (int)((UINT64_C(1) << 
					(QMAT_SHIFT + 11))/(aanscales[i]
					*qscale * quant_matrix[j]));
            		}
        	} else {
            		for (i = 0; i < 64; i++) {
				const int j = s->dsp.idct_permutation[i];
/* We can safely assume that 16 <= quant_matrix[i] <= 255
 * So 16           <= qscale * quant_matrix[i]             <= 7905
 * so (1<<19) / 16 >= (1<<19) / (qscale * quant_matrix[i]) >= (1<<19) / 7905
 * so 32768        >= (1<<19) / (qscale * quant_matrix[i]) >= 67 */
                		qmat[qscale][i] = (int)((uint64_t_C(1) << 
						QMAT_SHIFT_MMX) / (qscale 
							*quant_matrix[j]));
                		qmat16[qscale][0][i] = (1 << QMAT_SHIFT_MMX)
						/(qscale * quant_matrix[j]);

                		if (qmat16[qscale][0][i] == 0 || 
						qmat16[qscale][0][i] == 128*256)
					qmat16[qscale][0][i]=128*256-1;
                		qmat16[qscale][1][i]=ROUNDED_DIV(bias
						<<(16-QUANT_BIAS_SHIFT), 
						qmat16[qscale][0][i]);
            		}
        	}
    	}
}

static inline void encode_dc(MpegEncContext *s, int val, 
		uint8_t *huff_size, uint16_t *huff_code) {
	int mant, nbits;

	if (val == 0) {
		put_bits(&s->pb, huff_size[0], huff_code[0]);
	} else {
		mant = val;
		if (val < 0) {
			val = -val;
			mant--;
		}
        
		/* compute the log (XXX: optimize) */
		nbits = 0;
		while (val != 0) {
			val = val >> 1;
			nbits++;
		}
            
		put_bits(&s->pb, huff_size[nbits], huff_code[nbits]);
		put_bits(&s->pb, nbits, mant & ((1 << nbits) - 1));
	}
}

static void encode_block(MpegEncContext *s, DCTELEM *block, int n) {
	int mant, nbits, code, i, j;
	int component, dc, run, last_index, val;
	MJpegContext *m = s->mjpeg_ctx;
	uint8_t *huff_size_ac;
	uint16_t *huff_code_ac;
    
	/* DC coef */
	component = (n <= 3 ? 0 : n - 4 + 1);
	dc = block[0]; /* overflow is impossible */
	val = dc - s->last_dc[component];
 	if (n < 4) {
		encode_dc(s, val, m->huff_size_dc_luminance, 
				m->huff_code_dc_luminance);
		huff_size_ac = m->huff_size_ac_luminance;
		huff_code_ac = m->huff_code_ac_luminance;
	} else {
        	encode_dc(s, val, m->huff_size_dc_chrominance, 
				m->huff_code_dc_chrominance);
		huff_size_ac = m->huff_size_ac_chrominance;
		huff_code_ac = m->huff_code_ac_chrominance;
	}
	s->last_dc[component] = dc;
    
	/* AC coefs */
    
	run = 0;
	last_index = s->block_last_index[n];
	for (i = 1; i <= last_index; i++) {
		j = s->intra_scantable.permutated[i];
		val = block[j];
		if (val == 0) run++;
        	else {
			while (run >= 16) {
				put_bits(&s->pb, huff_size_ac[0xf0], 
						huff_code_ac[0xf0]);
				run -= 16;
			}
            		mant = val;
			if (val < 0) {
				val = -val;
                		mant--;
            		}
            
            		/* compute the log (XXX: optimize) */
            		nbits = 0;
			while (val != 0) {
				val = val >> 1;
				nbits++; 
			}
			code = (run << 4) | nbits;

			put_bits(&s->pb, huff_size_ac[code], 
					huff_code_ac[code]);
            		put_bits(&s->pb, nbits, mant & ((1 << nbits) - 1));
            		run = 0;
        	}
    	}

	/* output EOB only if not already 64 values */ 
	if (last_index < 63 || run != 0)
		put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);
}

static inline void clip_coeffs(MpegEncContext *s, DCTELEM *block, 
		int last_index) {
	int i;
	const int maxlevel= s->max_qcoeff;
	const int minlevel= s->min_qcoeff;

	for (i = 0; i <= last_index; i++) {
		const int j = s->intra_scantable.permutated[i];
		int level = block[j];
       
		if (level > maxlevel) level=maxlevel;
		else if(level < minlevel) level=minlevel;
		block[j]= level;
	}
}

/* End excessive code duplication **************************************/

typedef struct {
	struct MpegEncContext *s;
	int cheap_upsample;
	int bw;
	int y_ps;
	int u_ps;
	int v_ps;
	int y_rs;
	int u_rs;
	int v_rs;
} jpeg_enc_t;

/* this function is a reproduction of the one in mjpeg, it includes two
 * changes, it allows for black&white encoding (it skips the U and V
 * macroblocks and it outputs the huffman code for 'no change' (dc) and
 * 'all zero' (ac)) and it takes 4 macroblocks (422) instead of 6 (420) */
static void zr_mjpeg_encode_mb(jpeg_enc_t *j) {

	MJpegContext *m = j->s->mjpeg_ctx;

	encode_block(j->s, j->s->block[0], 0);
	encode_block(j->s, j->s->block[1], 1);
	if (j->bw) {
		/* U */
		put_bits(&j->s->pb, m->huff_size_dc_chrominance[0],
				m->huff_code_dc_chrominance[0]);
		put_bits(&j->s->pb, m->huff_size_ac_chrominance[0],
				m->huff_code_ac_chrominance[0]);
		/* V */
		put_bits(&j->s->pb, m->huff_size_dc_chrominance[0],
				m->huff_code_dc_chrominance[0]);
		put_bits(&j->s->pb, m->huff_size_ac_chrominance[0],
				m->huff_code_ac_chrominance[0]);
    	} else {
		/* we trick encode_block here so that it uses
		 * chrominance huffman tables instead of luminance ones 
		 * (see the effect of second argument of encode_block) */
		encode_block(j->s, j->s->block[2], 4); 
		encode_block(j->s, j->s->block[3], 5);
    	}
}

/* this function can take all kinds of YUV colorspaces
 * YV12, YVYU, UYVY. The necesary parameters must be set up by the caller
 * y_ps means "y pixel size", y_rs means "y row size".
 * For YUYV, for example, is u_buf = y_buf + 1, v_buf = y_buf + 3, 
 * y_ps = 2, u_ps = 4, v_ps = 4, y_rs = u_rs = v_rs.
 *
 *  The actual buffers must be passed with mjpeg_encode_frame, this is
 *  to make it possible to call encode on the buffer provided by the
 *  codec in draw_frame.
 *  
 * The data is straightened out at the moment it is put in DCT
 * blocks, there are therefore no spurious memcopies involved */
/* Notice that w must be a multiple of 16 and h must be a multiple of 8 */
/* We produce YUV422 jpegs, the colors must be subsampled horizontally,
 * if the colors are also subsampled vertically, then this function
 * performs cheap upsampling (better solution will be: a DCT that is
 * optimized in the case that every two rows are the same) */
/* cu = 0 means 'No cheap upsampling'
 * cu = 1 means 'perform cheap upsampling' */
/* The encoder doesn't know anything about interlacing, the halve height
 * needs to be passed and the double rowstride. Which field gets encoded
 * is decided by what buffers are passed to mjpeg_encode_frame */
static jpeg_enc_t *jpeg_enc_init(int w, int h, int y_psize, int y_rsize, 
		int u_psize, int u_rsize, int v_psize, int v_rsize,
		int cu, int q, int b) {
	jpeg_enc_t *j;
	int i = 0;
	VERBOSE("JPEG encoder init: %dx%d %d %d %d %d %d %d\n",
			w, h, y_psize, y_rsize, u_psize, 
			u_rsize, v_psize, v_rsize);

	j = malloc(sizeof(jpeg_enc_t));
	if (j == NULL) return NULL;

	j->s = malloc(sizeof(MpegEncContext));
	memset(j->s,0x00,sizeof(MpegEncContext));
	if (j->s == NULL) {
		free(j);
		return NULL;
	}

	/* info on how to access the pixels */
	j->y_ps = y_psize; 
	j->u_ps = u_psize; 
	j->v_ps = v_psize;
	j->y_rs = y_rsize; 
	j->u_rs = u_rsize; 
	j->v_rs = v_rsize;

	j->s->width = w;
	j->s->height = h;
	j->s->qscale = q;

	j->s->mjpeg_data_only_frames = 0;
	j->s->out_format = FMT_MJPEG;
	j->s->intra_only = 1;
	j->s->encoding = 1;
	j->s->pict_type = I_TYPE;
	j->s->y_dc_scale = 8;
	j->s->c_dc_scale = 8;

	j->s->mjpeg_write_tables = 1;
	j->s->mjpeg_vsample[0] = 1;
	j->s->mjpeg_vsample[1] = 1;
	j->s->mjpeg_vsample[2] = 1;
	j->s->mjpeg_hsample[0] = 2;
	j->s->mjpeg_hsample[1] = 1;
	j->s->mjpeg_hsample[2] = 1;

	j->cheap_upsample = cu;
	j->bw = b;

	if (mjpeg_init(j->s) < 0) {
		free(j->s);
		free(j);
		return NULL;
	}

	/* alloc bogus avctx to keep MPV_common_init from segfaulting */
	j->s->avctx = calloc(sizeof(*j->s->avctx), 1);

	/* make MPV_common_init allocate important buffers, like s->block */
	j->s->avctx->thread_count = 1;

	if (MPV_common_init(j->s) < 0) {
		free(j->s);
		free(j);
		return NULL;
	}

	/* correct the value for sc->mb_height */
	j->s->mb_height = j->s->height/8;
	j->s->mb_intra = 1;

	j->s->intra_matrix[0] = ff_mpeg1_default_intra_matrix[0];
	for (i = 1; i < 64; i++) 
		j->s->intra_matrix[i] = clip_uint8(
			(ff_mpeg1_default_intra_matrix[i]*j->s->qscale) >> 3);
	convert_matrix(j->s, j->s->q_intra_matrix, j->s->q_intra_matrix16, 
			j->s->intra_matrix, j->s->intra_quant_bias, 8, 8);
	return j;
}	

static int jpeg_enc_frame(jpeg_enc_t *j, unsigned char *y_data, 
		unsigned char *u_data, unsigned char *v_data, char *bufr) {
	int i, k, mb_x, mb_y, overflow;
	short int *dest;
	unsigned char *source;
	/* initialize the buffer */

	init_put_bits(&j->s->pb, bufr, 1024*256);

	mjpeg_picture_header(j->s);

	j->s->header_bits = put_bits_count(&j->s->pb);

	j->s->last_dc[0] = 128; 
	j->s->last_dc[1] = 128; 
	j->s->last_dc[2] = 128;

	for (mb_y = 0; mb_y < j->s->mb_height; mb_y++) {
		for (mb_x = 0; mb_x < j->s->mb_width; mb_x++) {
			/* conversion 8 to 16 bit and filling of blocks
			 * must be mmx optimized */
			/* fill 2 Y macroblocks and one U and one V */
			source = mb_y * 8 * j->y_rs + 
				16 * j->y_ps * mb_x + y_data;
			dest = j->s->block[0];
			for (i = 0; i < 8; i++) {
				for (k = 0; k < 8; k++) {
					dest[k] = source[k*j->y_ps];
				}
				dest += 8;
				source += j->y_rs;
			}
			source = mb_y * 8 * j->y_rs + 
				(16*mb_x + 8)*j->y_ps + y_data;
			dest = j->s->block[1];
			for (i = 0; i < 8; i++) {
				for (k = 0; k < 8; k++) {
					dest[k] = source[k*j->y_ps];
				}
				dest += 8;
				source += j->y_rs;
			}
			if (!j->bw && j->cheap_upsample) {
				source = mb_y*4*j->u_rs + 
					8*mb_x*j->u_ps + u_data;
				dest = j->s->block[2];
				for (i = 0; i < 4; i++) {
					for (k = 0; k < 8; k++) {
						dest[k] = source[k*j->u_ps];
						dest[k+8] = source[k*j->u_ps];
					}
					dest += 16;
					source += j->u_rs;
				}
				source = mb_y*4*j->v_rs + 
					8*mb_x*j->v_ps + v_data;
				dest = j->s->block[3];
				for (i = 0; i < 4; i++) {
					for (k = 0; k < 8; k++) {
						dest[k] = source[k*j->v_ps];
						dest[k+8] = source[k*j->v_ps];
					}
					dest += 16;
					source += j->u_rs;
				}
			} else if (!j->bw && !j->cheap_upsample) {
				source = mb_y*8*j->u_rs + 
					8*mb_x*j->u_ps + u_data;
				dest = j->s->block[2];
				for (i = 0; i < 8; i++) {
					for (k = 0; k < 8; k++) 
						dest[k] = source[k*j->u_ps];
					dest += 8;
					source += j->u_rs;
				}
				source = mb_y*8*j->v_rs + 
					8*mb_x*j->v_ps + v_data;
				dest = j->s->block[3];
				for (i = 0; i < 8; i++) {
					for (k = 0; k < 8; k++) 
						dest[k] = source[k*j->v_ps];
					dest += 8;
					source += j->u_rs;
				}
			}
			emms_c(); /* is this really needed? */

			j->s->block_last_index[0] = 
				j->s->dct_quantize(j->s, j->s->block[0], 
						0, 8, &overflow);
			if (overflow) clip_coeffs(j->s, j->s->block[0], 
					j->s->block_last_index[0]);
			j->s->block_last_index[1] = 
				j->s->dct_quantize(j->s, j->s->block[1], 
						1, 8, &overflow);
			if (overflow) clip_coeffs(j->s, j->s->block[1], 
					j->s->block_last_index[1]);

			if (!j->bw) {
				j->s->block_last_index[4] =
					j->s->dct_quantize(j->s, j->s->block[2],
							4, 8, &overflow);
				if (overflow) clip_coeffs(j->s, j->s->block[2], 
						j->s->block_last_index[2]);
				j->s->block_last_index[5] =
					j->s->dct_quantize(j->s, j->s->block[3],
							5, 8, &overflow);
				if (overflow) clip_coeffs(j->s, j->s->block[3], 
						j->s->block_last_index[3]);
			}
			zr_mjpeg_encode_mb(j);
		}
	}
	emms_c();
	mjpeg_picture_trailer(j->s);
	flush_put_bits(&j->s->pb);	

	if (j->s->mjpeg_write_tables == 1)
		j->s->mjpeg_write_tables = 0;
	
	return pbBufPtr(&(j->s->pb)) - j->s->pb.buf;
}

static void jpeg_enc_uninit(jpeg_enc_t *j) {
	mjpeg_close(j->s);
	free(j->s);
	free(j);
}

struct vf_priv_s {
	jpeg_enc_t *j;
	unsigned char buf[256*1024];
	int bw, fd, hdec, vdec;
	int fields;
	int y_stride;
	int c_stride;
	int quality;
	int maxwidth;
	int maxheight;
};

static int config(struct vf_instance_s* vf, int width, int height, int d_width,
		int d_height, unsigned int flags, unsigned int outfmt){
	struct vf_priv_s *priv = vf->priv;
	float aspect_decision;
	int stretchx, stretchy, err = 0, maxstretchx = 4;
	priv->fields = 1;

	VERBOSE("config() called\n");

	if (priv->j) {
		VERBOSE("re-configuring, resetting JPEG encoder\n");
		jpeg_enc_uninit(priv->j);
		priv->j = NULL;
	}
	
	aspect_decision = ((float)d_width/(float)d_height)/
		((float)width/(float)height);
	
	if (aspect_decision > 1.8 && aspect_decision < 2.2) {
		VERBOSE("should correct aspect by stretching x times 2, %d %d\n", 2*width, priv->maxwidth);
		if (2*width <= priv->maxwidth) {
			d_width = 2*width;
			d_height = height;
			maxstretchx = 2;
		} else {
			WARNING("unable to correct aspect by stretching, because resulting X will be too large, aspect correction by decimating y not yet implemented\n");
			d_width = width;
			d_height = height;
		}
		/* prestretch movie */
	} else {
		/* uncorrecting output for now */
		d_width = width;
		d_height = height;
	}
	/* make the scaling decision
	 * we are capable of stretching the image in the horizontal
	 * direction by factors 1, 2 and 4
	 * we can stretch the image in the vertical direction by a 
	 * factor of 1 and 2 AND we must decide about interlacing */
	if (d_width > priv->maxwidth/2 || height > priv->maxheight/2 
			|| maxstretchx == 1) {
		stretchx = 1;
		stretchy = 1;
		priv->fields = 2;
		if (priv->vdec == 2) {
			priv->fields = 1;
		} else if (priv->vdec == 4) {
			priv->fields = 1;
			stretchy = 2;
		}
		if (priv->hdec > maxstretchx) {
			if (priv->fd) {
				WARNING("horizontal decimation too high, changing to %d (use fd to keep hdec=%d)\n", maxstretchx, priv->hdec);
				priv->hdec = maxstretchx;
			}
		}
		stretchx = priv->hdec;
	} else if (d_width > priv->maxwidth/4 ||
			height > priv->maxheight/4 ||
			maxstretchx == 2) {
		stretchx = 2;
		stretchy = 1;
		priv->fields = 1;
		if (priv->vdec == 2) {
			stretchy = 2;
		} else if (priv->vdec == 4) {
			if (!priv->fd) {
				WARNING("vertical decimation too high, changing to 2 (use fd to keep vdec=4)\n");
				priv->vdec = 2;
			}
			stretchy = 2;
		}
		if (priv->hdec == 2) {
			stretchx = 4;
		} else if (priv->hdec == 4) {
			if (priv->fd) {
				WARNING("horizontal decimation too high, changing to 2 (use fd to keep hdec=4)\n");
				priv->hdec = 2;
			}
			stretchx = 4;
		}
	} else {
		/* output image is maximally stretched */
		stretchx = 4;
		stretchy = 2;
		priv->fields = 1;
		if (priv->vdec != 1 && !priv->fd) {
			WARNING("vertical decimation too high, changing to 1 (use fd to keep vdec=%d)\n", priv->vdec);
			priv->vdec = 1;
		}
		if (priv->hdec != 1 && !priv->fd) {
			WARNING("horizontal decimation too high, changing to 1 (use fd to keep hdec=%d)\n", priv->hdec);
			priv->hdec = 1;
		}
	}
	
	VERBOSE("generated JPEG's %dx%s%d%s, stretched to %dx%d\n", 
			width/priv->hdec, (priv->fields == 2) ? "(" : "", 
			height/(priv->vdec*priv->fields),
			(priv->fields == 2) ? "x2)" : "",
			(width/priv->hdec)*stretchx,
			(height/(priv->vdec*priv->fields))*
			stretchy*priv->fields);


	if ((width/priv->hdec)*stretchx > priv->maxwidth || 
			(height/(priv->vdec*priv->fields))*
			 stretchy*priv->fields  > priv->maxheight) {
		ERROR("output dimensions too large (%dx%d), max (%dx%d) insert crop to fix\n", (width/priv->hdec)*stretchx, (height/(priv->vdec*priv->fields))*stretchy*priv->fields, priv->maxwidth, priv->maxheight);
		err = 1;
	}

	if (width%(16*priv->hdec) != 0) {
		ERROR("width must be a multiple of 16*hdec (%d), use expand\n", 
				priv->hdec*16);
		err = 1;
	}

	if (height%(8*priv->fields*priv->vdec) != 0) {
		ERROR("height must be a multiple of 8*fields*vdec (%d),"
				" use expand\n", priv->vdec*priv->fields*8);
		err = 1;
	}

	if (err) return 0;

	priv->y_stride = width;
	priv->c_stride = width/2;
	priv->j = jpeg_enc_init(width, height/priv->fields, 1, 
			priv->fields*priv->y_stride, 1, 
			priv->fields*priv->c_stride, 1, 
			priv->fields*priv->c_stride, 1, 
			priv->quality, priv->bw);

	if (!priv->j) return 0;
	return vf_next_config(vf, width, height, d_width, d_height, flags, 
		(priv->fields == 2) ? IMGFMT_ZRMJPEGIT : IMGFMT_ZRMJPEGNI); 
}

static int put_image(struct vf_instance_s* vf, mp_image_t *mpi){
	struct vf_priv_s *priv = vf->priv;
	int size = 0;
	int i;
	mp_image_t* dmpi; 
	for (i = 0; i < priv->fields; i++) 
		size += jpeg_enc_frame(priv->j, 
				mpi->planes[0] + i*priv->y_stride,
				mpi->planes[1] + i*priv->c_stride, 
				mpi->planes[2] + i*priv->c_stride, 
				priv->buf + size);

	dmpi = vf_get_image(vf->next, IMGFMT_ZRMJPEGNI,
			MP_IMGTYPE_EXPORT, 0, mpi->w, mpi->h);
	dmpi->planes[0] = (uint8_t*)priv->buf;
	dmpi->planes[1] = (uint8_t*)size;
	return vf_next_put_image(vf,dmpi); 
}

static int query_format(struct vf_instance_s* vf, unsigned int fmt){
	VERBOSE("query_format() called\n");

	switch (fmt) { 
		case IMGFMT_YV12:
		case IMGFMT_YUY2:
			/* strictly speaking the output format of
			 * this filter will be known after config(),
			 * but everything that supports IMGFMT_ZRMJPEGNI
			 * should also support all other IMGFMT_ZRMJPEG* */
			return vf_next_query_format(vf, IMGFMT_ZRMJPEGNI);
	}

	return 0;
}

static void uninit(vf_instance_t *vf) {
	struct vf_priv_s *priv = vf->priv;
	VERBOSE("uninit() called\n");
	if (priv->j) jpeg_enc_uninit(priv->j);
	free(priv);
}

static int open(vf_instance_t *vf, char* args){
	struct vf_priv_s *priv;
	VERBOSE("open() called: args=\"%s\"\n", args);

	vf->config = config;
	vf->put_image = put_image;
	vf->query_format = query_format;
	vf->uninit = uninit;

	priv = vf->priv = calloc(sizeof(*priv), 1);
	if (!vf->priv) {
		ERROR("out of memory error\n");
		return 0;
	}

	/* maximum displayable size by zoran card, these defaults 
	 * are for my own zoran card in PAL mode, these can be changed
	 * by filter options. But... in an ideal world these values would
	 * be queried from the vo device itself... */
	priv->maxwidth = 768;
	priv->maxheight = 576;

	priv->quality = 2;
	priv->hdec = 1;
	priv->vdec = 1;

	/* if libavcodec is already initialized, we must not initialize it 
	 * again, but if it is not initialized then we mustinitialize it now. */
	if (!avcodec_inited) {
		/* we need to initialize libavcodec */
		avcodec_init();
		avcodec_register_all();
		avcodec_inited=1;
	}
	
	if (args) {
		char *arg, *tmp, *ptr, junk;
		int last = 0, input;

		/* save arguments, to be able to safely modify them */
		arg = strdup(args);
		if (!arg) {
			ERROR("out of memory, this is bad\n");
			return 0;
		}

		tmp = ptr = arg;
		do {
			while (*tmp != ':' && *tmp) tmp++;
			if (*tmp == ':') *tmp++ = '\0';
			else last = 1;
			VERBOSE("processing filter option \"%s\"\n", ptr);
			/* These options deal with the maximum output
			 * resolution of the zoran card. These should
			 * be queried from the vo device, but it is currently
			 * too difficult, so the user should tell the filter */
			if (!strncmp("maxheight=", ptr, 10)) {
				if (sscanf(ptr+10, "%d%c", &input, &junk) != 1) 
						ERROR(
		"error parsing parameter to \"maxheight=\", \"%s\", ignoring\n"
								, ptr + 10);
				else {
					priv->maxheight = input;
					VERBOSE("setting maxheight to %d\n",
							priv->maxheight);
				}
			} else if (!strncmp("quality=", ptr, 8)) {
				if (sscanf(ptr+8, "%d%c", &input, &junk) != 1)
					ERROR(
		"error parsing parameter to \"quality=\", \"%s\", ignoring\n"
								, ptr + 8);
				else if (input < 1 || input > 20)
					ERROR(
		"parameter to \"quality=\" out of range (1..20), %d\n", input);
				else {
					priv->quality = input;
					VERBOSE("setting JPEG quality to %d\n",
							priv->quality);
				}
			} else if (!strncmp("maxwidth=", ptr, 9)) {
				if (sscanf(ptr+9, "%d%c", &input, &junk) != 1) 
					ERROR(
		"error parsing parameter to \"maxwidth=\", \"%s\", ignoring\n"
								, ptr + 9);
				else {
					priv->maxwidth = input;
					VERBOSE("setting maxwidth to %d\n",
							priv->maxwidth);
				}
			} else if (!strncmp("hdec=", ptr, 5)) {
				if (sscanf(ptr+5, "%d%c", &input, &junk) != 1) 
					ERROR(
		"error parsing parameter to \"hdec=\", \"%s\", ignoring\n"
								, ptr + 9);
				else if (input != 1 && input != 2 && input != 4)
					ERROR(
		"illegal parameter to \"hdec=\", %d, should be 1, 2 or 4", 
								input);
				else {
					priv->hdec = input;
					VERBOSE(
		"setting horizontal decimation to %d\n", priv->maxwidth);
				}
			} else if (!strncmp("vdec=", ptr, 5)) {
				if (sscanf(ptr+5, "%d%c", &input, &junk) != 1) 
					ERROR(
		"error parsing parameter to \"vdec=\", \"%s\", ignoring\n"
								, ptr + 9);
				else if (input != 1 && input != 2 && input != 4)
					ERROR(
		"illegal parameter to \"vdec=\", %d, should be 1, 2 or 4", 
								input);
				else {
					priv->vdec = input;
					VERBOSE(
			"setting vertical decimation to %d\n", priv->maxwidth);
				}
			} else if (!strcasecmp("dc10+-PAL", ptr) ||
					!strcasecmp("dc10-PAL", ptr)) {
				priv->maxwidth = 768;
				priv->maxheight = 576;
				VERBOSE("setting DC10(+) PAL profile\n");
			} else if (!strcasecmp("fd", ptr)) {
				priv->fd = 1;
				VERBOSE("forcing decimation\n");
			} else if (!strcasecmp("nofd", ptr)) {
				priv->fd = 0;
				VERBOSE("decimate only if beautiful\n");
			} else if (!strcasecmp("bw", ptr)) {
				priv->bw = 1;
				VERBOSE("setting black and white encoding\n");
			} else if (!strcasecmp("color", ptr)) {
				priv->bw = 0;
				VERBOSE("setting color encoding\n");
			} else if (!strcasecmp("dc10+-NTSC", ptr) ||
					!strcasecmp("dc10-NTSC", ptr)) {
				priv->maxwidth = 640;
				priv->maxheight = 480;
				VERBOSE("setting DC10(+) NTSC profile\n");
			} else if (!strcasecmp("buz-PAL", ptr) ||
					!strcasecmp("lml33-PAL", ptr)) {
				priv->maxwidth = 720;
				priv->maxheight = 576;
				VERBOSE("setting buz/lml33 PAL profile\n");
			} else if (!strcasecmp("buz-NTSC", ptr) ||
					!strcasecmp("lml33-NTSC", ptr)) {
				priv->maxwidth = 720;
				priv->maxheight = 480;
				VERBOSE("setting buz/lml33 NTSC profile\n");
			} else {
				WARNING("ignoring unknown filter option " 
						"\"%s\", or missing argument\n",
						ptr);
			}
			ptr = tmp;
		} while (!last);

		free(arg);
	}


	return 1;
}

vf_info_t vf_info_zrmjpeg = {
    "realtime zoran MJPEG encoding",
    "zrmjpeg",
    "Rik Snel",
    "",
    open,
    NULL
};