mjpeg.c

Trolltech公司发布的图形界面操作系统。可在qt-embedded-2.3.10平台上编译为嵌入式图形界面操作系统。

    *data_size = 0;

    /* no supplementary picture */
    if (buf_size == 0)
        return 0;

    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);
		    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 == 0xff) src++;

			    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);
		} else if (s->first_picture) {
		    /* APP fields */
		    if (start_code >= 0xe0 && start_code <= 0xef)
			mjpeg_decode_app(s);
		    /* Comment */
		    else if (start_code == COM)
			mjpeg_decode_com(s);
		}

                switch(start_code) {
                case SOI:
		    s->restart_interval = 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 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);
                        avctx->height = s->height;
                        if (s->interlaced)
                            avctx->height *= 2;
                        avctx->width = s->width;

                        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;

    *data_size = 0;

    /* no supplementary picture */
    if (buf_size == 0)
        return 0;

    buf_ptr = buf;
    buf_end = buf + buf_size;
    
read_header:
    /* reset on every SOI */
    s->restart_interval = 0;

    init_get_bits(&hgb, buf_ptr, /*buf_size*/(buf_end - buf_ptr)*8);

    skip_bits(&hgb, 32); /* reserved zeros */
    
    if (get_bits(&hgb, 32) != be2me_32(ff_get_fourcc("mjpg")))
    {
	dprintf("not mjpeg-b (bad fourcc)\n");
	return 0;
    }

    field_size = get_bits(&hgb, 32); /* field size */
    dprintf("field size: 0x%x\n", field_size);
    skip_bits(&hgb, 32); /* padded field size */
    second_field_offs = get_bits(&hgb, 32);
    dprintf("second field offs: 0x%x\n", second_field_offs);
    if (second_field_offs)
	s->interlaced = 1;

    dqt_offs = get_bits(&hgb, 32);
    dprintf("dqt offs: 0x%x\n", dqt_offs);
    if (dqt_offs)
    {
	init_get_bits(&s->gb, buf+dqt_offs, (buf_end - (buf+dqt_offs))*8);
	s->start_code = DQT;
	mjpeg_decode_dqt(s);
    }
    
    dht_offs = get_bits(&hgb, 32);
    dprintf("dht offs: 0x%x\n", dht_offs);
    if (dht_offs)
    {
	init_get_bits(&s->gb, buf+dht_offs, (buf_end - (buf+dht_offs))*8);
	s->start_code = DHT;
	mjpeg_decode_dht(s);
    }

    sof_offs = get_bits(&hgb, 32);
    dprintf("sof offs: 0x%x\n", sof_offs);
    if (sof_offs)
    {
	init_get_bits(&s->gb, buf+sof_offs, (buf_end - (buf+sof_offs))*8);
	s->start_code = SOF0;
	if (mjpeg_decode_sof(s) < 0)
	    return -1;
    }

    sos_offs = get_bits(&hgb, 32);
    dprintf("sos offs: 0x%x\n", sos_offs);
    if (sos_offs)
    {
//	init_get_bits(&s->gb, buf+sos_offs, (buf_end - (buf+sos_offs))*8);
	init_get_bits(&s->gb, buf+sos_offs, field_size*8);
	s->start_code = SOS;
	mjpeg_decode_sos(s);
    }

    skip_bits(&hgb, 32); /* start of data offset */

    if (s->interlaced) {
        s->bottom_field ^= 1;
        /* if not bottom field, do not output image yet */
        if (s->bottom_field && second_field_offs)
	{
	    buf_ptr = buf + second_field_offs;
	    second_field_offs = 0;
	    goto read_header;
    	}
    }

    //XXX FIXME factorize, this looks very similar to the EOI code

    *picture= s->picture;
    *data_size = sizeof(AVFrame);
    avctx->height = s->height;
    if (s->interlaced)
        avctx->height *= 2;
    avctx->width = s->width;
    
    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(avctx, AV_LOG_DEBUG, "QP: %d\n", picture->quality);
        picture->quality*= FF_QP2LAMBDA;
    }

    return buf_ptr - buf;
}

#include "sp5x.h"

static int sp5x_decode_frame(AVCodecContext *avctx, 
                              void *data, int *data_size,
                              uint8_t *buf, int buf_size)
{
#if 0
    MJpegDecodeContext *s = avctx->priv_data;
#endif
    const int qscale = 5;
    uint8_t *buf_ptr, *buf_end, *recoded;
    int i = 0, j = 0;

    *data_size = 0;

    /* no supplementary picture */
    if (buf_size == 0)
        return 0;

    if (!avctx->width || !avctx->height)
	return -1;

    buf_ptr = buf;
    buf_end = buf + buf_size;

#if 1
    recoded = av_mallocz(buf_size + 1024);
    if (!recoded)
	return -1;

    /* SOI */
    recoded[j++] = 0xFF;
    recoded[j++] = 0xD8;

    memcpy(recoded+j, &sp5x_data_dqt[0], sizeof(sp5x_data_dqt));
    memcpy(recoded+j+5, &sp5x_quant_table[qscale * 2], 64);
    memcpy(recoded+j+70, &sp5x_quant_table[(qscale * 2) + 1], 64);
    j += sizeof(sp5x_data_dqt);

    memcpy(recoded+j, &sp5x_data_dht[0], sizeof(sp5x_data_dht));
    j += sizeof(sp5x_data_dht);

    memcpy(recoded+j, &sp5x_data_sof[0], sizeof(sp5x_data_sof));
    recoded[j+5] = (avctx->height >> 8) & 0xFF;
    recoded[j+6] = avctx->height & 0xFF;
    recoded[j+7] = (avctx->width >> 8) & 0xFF;
    recoded[j+8] = avctx->width & 0xFF;
    j += sizeof(sp5x_data_sof);

    memcpy(recoded+j, &sp5x_data_sos[0], sizeof(sp5x_data_sos));
    j += sizeof(sp5x_data_sos);

    for (i = 14; i < buf_size && j < buf_size+1024-2; i++)
    {
	recoded[j++] = buf[i];
	if (buf[i] == 0xff)
	    recoded[j++] = 0;
    }

    /* EOI */
    recoded[j++] = 0xFF;
    recoded[j++] = 0xD9;

    i = mjpeg_decode_frame(avctx, data, data_size, recoded, j);

    av_free(recoded);

#else
    /* SOF */
    s->bits = 8;
    s->width = avctx->width;
    s->height = avctx->height;
    s->nb_components = 3;
    s->component_id[0] = 0;
    s->h_count[0] = 2;
    s->v_count[0] = 2;
    s->quant_index[0] = 0;
    s->component_id[1] = 1;
    s->h_count[1] = 1;
    s->v_count[1] = 1;
    s->quant_index[1] = 1;
    s->component_id[2] = 2;
    s->h_count[2] = 1;
    s->v_count[2] = 1;
    s->quant_index[2] = 1;
    s->h_max = 2;
    s->v_max = 2;
    
    s->qscale_table = av_mallocz((s->width+15)/16);
    avctx->pix_fmt = PIX_FMT_YUV420P;
    s->interlaced = 0;
    
    s->picture.reference = 0;
    if (avctx->get_buffer(avctx, &s->picture) < 0)
    {
	fprintf(stderr, "get_buffer() failed\n");
	return -1;
    }

    s->picture.pict_type = I_TYPE;
    s->picture.key_frame = 1;

    for (i = 0; i < 3; i++)
	s->linesize[i] = s->picture.linesize[i] << s->interlaced;

    /* DQT */
    for (i = 0; i < 64; i++)
    {
	j = s->scantable.permutated[i];
	s->quant_matrixes[0][j] = sp5x_quant_table[(qscale * 2) + i];
    }
    s->qscale[0] = FFMAX(
	s->quant_matrixes[0][s->scantable.permutated[1]],
	s->quant_matrixes[0][s->scantable.permutated[8]]) >> 1;

    for (i = 0; i < 64; i++)
    {
	j = s->scantable.permutated[i];
	s->quant_matrixes[1][j] = sp5x_quant_table[(qscale * 2) + 1 + i];
    }
    s->qscale[1] = FFMAX(
	s->quant_matrixes[1][s->scantable.permutated[1]],
	s->quant_matrixes[1][s->scantable.permutated[8]]) >> 1;

    /* DHT */

    /* SOS */
    s->comp_index[0] = 0;
    s->nb_blocks[0] = s->h_count[0] * s->v_count[0];
    s->h_scount[0] = s->h_count[0];
    s->v_scount[0] = s->v_count[0];
    s->dc_index[0] = 0;
    s->ac_index[0] = 0;

    s->comp_index[1] = 1;
    s->nb_blocks[1] = s->h_count[1] * s->v_count[1];
    s->h_scount[1] = s->h_count[1];
    s->v_scount[1] = s->v_count[1];
    s-