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📄 mjpeg.c

📁 mpeg4 video codec mpeg4 video codec
💻 C
📖 第 1 页 / 共 5 页
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	skip_bits(&s->gb, 32);	len -= 10;#endif//	if (s->interlace_polarity)//	    printf("mjpeg: interlace polarity: %d\n", s->interlace_polarity);	goto out;    }    //    len -= 2;        if (id == ff_get_fourcc("JFIF"))    {	int t_w, t_h, v1, v2;	skip_bits(&s->gb, 8); /* the trailing zero-byte */	v1= get_bits(&s->gb, 8);        v2= get_bits(&s->gb, 8);        skip_bits(&s->gb, 8);        s->avctx->sample_aspect_ratio.num= get_bits(&s->gb, 16);        s->avctx->sample_aspect_ratio.den= get_bits(&s->gb, 16);        if (s->avctx->debug & FF_DEBUG_PICT_INFO)            av_log(s->avctx, AV_LOG_INFO, "mjpeg: JFIF header found (version: %x.%x) SAR=%d/%d\n",                v1, v2,                s->avctx->sample_aspect_ratio.num,                s->avctx->sample_aspect_ratio.den            );	t_w = get_bits(&s->gb, 8);	t_h = get_bits(&s->gb, 8);	if (t_w && t_h)	{	    /* skip thumbnail */	    if (len-10-(t_w*t_h*3) > 0)		len -= t_w*t_h*3;	}	len -= 10;	goto out;    }        if (id == ff_get_fourcc("Adob") && (get_bits(&s->gb, 8) == 'e'))    {        if (s->avctx->debug & FF_DEBUG_PICT_INFO)	av_log(s->avctx, AV_LOG_INFO, "mjpeg: Adobe header found\n");	skip_bits(&s->gb, 16); /* version */	skip_bits(&s->gb, 16); /* flags0 */	skip_bits(&s->gb, 16); /* flags1 */	skip_bits(&s->gb, 8); /* transform */	len -= 7;	goto out;    }        if (id == ff_get_fourcc("LJIF")){        if (s->avctx->debug & FF_DEBUG_PICT_INFO)        av_log(s->avctx, AV_LOG_INFO, "Pegasus lossless jpeg header found\n");	skip_bits(&s->gb, 16); /* version ? */	skip_bits(&s->gb, 16); /* unknwon always 0? */	skip_bits(&s->gb, 16); /* unknwon always 0? */	skip_bits(&s->gb, 16); /* unknwon always 0? */        switch( get_bits(&s->gb, 8)){        case 1:            s->rgb= 1;            s->pegasus_rct=0;            break;        case 2:            s->rgb= 1;            s->pegasus_rct=1;            break;        default:            av_log(s->avctx, AV_LOG_ERROR, "unknown colorspace\n");        }        len -= 9;        goto out;    }        /* Apple MJPEG-A */    if ((s->start_code == APP1) && (len > (0x28 - 8)))    {	id = (get_bits(&s->gb, 16) << 16) | get_bits(&s->gb, 16);	id = be2me_32(id);	len -= 4;	if (id == ff_get_fourcc("mjpg")) /* Apple MJPEG-A */	{#if 0	    skip_bits(&s->gb, 32); /* field size */	    skip_bits(&s->gb, 32); /* pad field size */	    skip_bits(&s->gb, 32); /* next off */	    skip_bits(&s->gb, 32); /* quant off */	    skip_bits(&s->gb, 32); /* huff off */	    skip_bits(&s->gb, 32); /* image off */	    skip_bits(&s->gb, 32); /* scan off */	    skip_bits(&s->gb, 32); /* data off */#endif            if (s->avctx->debug & FF_DEBUG_PICT_INFO)		av_log(s->avctx, AV_LOG_INFO, "mjpeg: Apple MJPEG-A header found\n");	}    }out:    /* slow but needed for extreme adobe jpegs */    if (len < 0)	av_log(s->avctx, AV_LOG_ERROR, "mjpeg: error, decode_app parser read over the end\n");    while(--len > 0)	skip_bits(&s->gb, 8);    return 0;}static int mjpeg_decode_com(MJpegDecodeContext *s){    int len = get_bits(&s->gb, 16);    if (len >= 2 && 8*len - 16 + get_bits_count(&s->gb) <= s->gb.size_in_bits) {	uint8_t *cbuf = av_malloc(len - 1);	if (cbuf) {	    int i;	    for (i = 0; i < len - 2; i++)	cbuf[i] = get_bits(&s->gb, 8);	    if (i > 0 && cbuf[i-1] == '\n')	cbuf[i-1] = 0;    else	cbuf[i] = 0;            if(s->avctx->debug & FF_DEBUG_PICT_INFO)	    av_log(s->avctx, AV_LOG_INFO, "mjpeg comment: '%s'\n", cbuf);    /* buggy avid, it puts EOI only at every 10th frame */    if (!strcmp(cbuf, "AVID"))    {	s->buggy_avid = 1;//	if (s->first_picture)//	    printf("mjpeg: workarounding buggy AVID\n");    }            else if(!strcmp(cbuf, "CS=ITU601")){                s->cs_itu601= 1;            }        av_free(cbuf);	}    }    return 0;}#if 0static int valid_marker_list[] ={        /* 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f *//* 0 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 1 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 2 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 3 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 4 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 5 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 6 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 7 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 8 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* 9 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* a */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* b */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,/* c */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,/* d */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,/* e */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,/* f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,}#endif/* return the 8 bit start code value and update the search   state. Return -1 if no start code found */static int find_marker(uint8_t **pbuf_ptr, uint8_t *buf_end){    uint8_t *buf_ptr;    unsigned int v, v2;    int val;#ifdef DEBUG    int skipped=0;#endif    buf_ptr = *pbuf_ptr;        while (buf_ptr < buf_end) {            v = *buf_ptr++;	v2 = *buf_ptr;        if ((v == 0xff) && (v2 >= 0xc0) && (v2 <= 0xfe) && buf_ptr < buf_end) {	    val = *buf_ptr++;                goto found;            }#ifdef DEBUG	skipped++;#endif        }        val = -1;found:#ifdef DEBUG    dprintf("find_marker skipped %d bytes\n", skipped);#endif    *pbuf_ptr = buf_ptr;    return val;}static int mjpeg_decode_frame(AVCodecContext *avctx,                               void *data, int *data_size,                              uint8_t *buf, int buf_size){    MJpegDecodeContext *s = avctx->priv_data;    uint8_t *buf_end, *buf_ptr;    int start_code;    AVFrame *picture = data;    buf_ptr = buf;    buf_end = buf + buf_size;    while (buf_ptr < buf_end) {        /* find start next marker */        start_code = find_marker(&buf_ptr, buf_end);	{	    /* EOF */            if (start_code < 0) {		goto the_end;        } else {                dprintf("marker=%x avail_size_in_buf=%d\n", start_code, buf_end - buf_ptr);				if ((buf_end - buf_ptr) > s->buffer_size)		{		    av_free(s->buffer);		    s->buffer_size = buf_end-buf_ptr;                    s->buffer = av_malloc(s->buffer_size + FF_INPUT_BUFFER_PADDING_SIZE);		    dprintf("buffer too small, expanding to %d bytes\n",			s->buffer_size);		}				/* unescape buffer of SOS */		if (start_code == SOS)		{		    uint8_t *src = buf_ptr;		    uint8_t *dst = s->buffer;		    while (src<buf_end)		    {			uint8_t x = *(src++);						*(dst++) = x;			if (x == 0xff)			{                            while(src<buf_end && x == 0xff)                                x = *(src++);			    if (x >= 0xd0 && x <= 0xd7)				*(dst++) = x;			    else if (x)				break;			}		    }		    init_get_bits(&s->gb, s->buffer, (dst - s->buffer)*8);		    		    dprintf("escaping removed %d bytes\n",			(buf_end - buf_ptr) - (dst - s->buffer));		}		else		    init_get_bits(&s->gb, buf_ptr, (buf_end - buf_ptr)*8);				s->start_code = start_code;                if(s->avctx->debug & FF_DEBUG_STARTCODE){                    av_log(s->avctx, AV_LOG_DEBUG, "startcode: %X\n", start_code);                }		/* process markers */		if (start_code >= 0xd0 && start_code <= 0xd7) {		    dprintf("restart marker: %d\n", start_code&0x0f);		    /* APP fields */		} else if (start_code >= APP0 && start_code <= APP15) {			mjpeg_decode_app(s);		    /* Comment */		} else if (start_code == COM){			mjpeg_decode_com(s);		}                switch(start_code) {                case SOI:		    s->restart_interval = 0;                    //reset_ls_coding_parameters(s, 1);		    s->restart_count = 0;                    /* nothing to do on SOI */                    break;                case DQT:                    mjpeg_decode_dqt(s);                    break;                case DHT:                    if(mjpeg_decode_dht(s) < 0){                        av_log(s->avctx, AV_LOG_ERROR, "huffman table decode error\n");                        return -1;                    }                    break;                case SOF0:                    s->lossless=0;                    if (mjpeg_decode_sof(s) < 0) 			return -1;                    break;                case SOF3:                    s->lossless=1;                    if (mjpeg_decode_sof(s) < 0) 			return -1;                    break;                case SOF48:                    s->lossless=1;                    s->ls=1;                    if (mjpeg_decode_sof(s) < 0)                        return -1;                    break;/*                case LSE:                    if (decode_lse(s) < 0)                        return -1;                    break;*/		case EOI:		    if ((s->buggy_avid && !s->interlaced) || s->restart_interval)                         break;eoi_parser:		    {                        if (s->interlaced) {                            s->bottom_field ^= 1;                            /* if not bottom field, do not output image yet */                            if (s->bottom_field)                                goto not_the_end;                        }                        *picture = s->picture;                        *data_size = sizeof(AVFrame);                        if(!s->lossless){                            picture->quality= FFMAX(FFMAX(s->qscale[0], s->qscale[1]), s->qscale[2]);                             picture->qstride= 0;                            picture->qscale_table= s->qscale_table;                            memset(picture->qscale_table, picture->quality, (s->width+15)/16);                            if(avctx->debug & FF_DEBUG_QP)                                av_log(s->avctx, AV_LOG_DEBUG, "QP: %d\n", picture->quality);                            picture->quality*= FF_QP2LAMBDA;                        }                                                goto the_end;                    }                    break;                case SOS:                    mjpeg_decode_sos(s);		    /* buggy avid puts EOI every 10-20th frame */		    /* if restart period is over process EOI */		    if ((s->buggy_avid && !s->interlaced) || s->restart_interval)			goto eoi_parser;                    break;		case DRI:		    mjpeg_decode_dri(s);		    break;		case SOF1:		case SOF2:		case SOF5:		case SOF6:		case SOF7:		case SOF9:		case SOF10:		case SOF11:		case SOF13:		case SOF14:		case SOF15:		case JPG:		    av_log(s->avctx, AV_LOG_ERROR, "mjpeg: unsupported coding type (%x)\n", start_code);		    break;//		default://		    printf("mjpeg: unsupported marker (%x)\n", start_code);//		    break;                }not_the_end:		/* eof process start code */		buf_ptr += (get_bits_count(&s->gb)+7)/8;		dprintf("marker parser used %d bytes (%d bits)\n",		    (get_bits_count(&s->gb)+7)/8, get_bits_count(&s->gb));		}        }    } the_end:    dprintf("mjpeg decode frame unused %d bytes\n", buf_end - buf_ptr);//    return buf_end - buf_ptr;    return buf_ptr - buf;}static int mjpegb_decode_frame(AVCodecContext *avctx,                               void *data, int *data_size,                              uint8_t *buf, int buf_size){    MJpegDecodeContext *s = avctx->priv_data;    uint8_t *buf_end, *buf_ptr;    AVFrame *picture = data;    GetBitContext hgb; /* for the header */    uint32_t dqt_offs, dht_offs, sof_offs, sos_offs, second_field_offs;    uint32_t field_size, sod_offs;    buf_ptr = buf;    buf_end = buf + buf_size;    read_header:    /* reset on every SOI */    s->restart_interval = 0;    s->restart_count = 0;    s->mjpb_skiptosod = 0;    init_get_bits(&hgb, buf_ptr, /*buf_size*/(buf_end - buf_ptr)*8);    skip_bits(&hgb, 32); /* reserved zeros */        if (get_bits_long(&hgb, 32) != be2me_32(ff_get_fourcc("mjpg")))    {	dpri

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