s->min_qcoeff=-1023; s->max_qcoeff= 1023;
int mjpeg_init(MpegEncContext *s){    MJpegContext *m;        m = malloc(sizeof(MJpegContext));    if (!m)        return -1;    /* build all the huffman tables */    build_huffman_codes(m->huff_size_dc_luminance,                        m->huff_code_dc_luminance,                        bits_dc_luminance,                        val_dc_luminance);    build_huffman_codes(m->huff_size_dc_chrominance,                        m->huff_code_dc_chrominance,                        bits_dc_chrominance,                        val_dc_chrominance);    build_huffman_codes(m->huff_size_ac_luminance,                        m->huff_code_ac_luminance,                        bits_ac_luminance,                        val_ac_luminance);    build_huffman_codes(m->huff_size_ac_chrominance,                        m->huff_code_ac_chrominance,                        bits_ac_chrominance,                        val_ac_chrominance);        s->mjpeg_ctx = m;    return 0;}