mov.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。

                    color_dec = 256 / (color_count - 1);
                    for (j = 0; j < color_count; j++) {
                        r = g = b = color_index;
                        c->palette_control.palette[j] =
                            (r << 16) | (g << 8) | (b);
                        color_index -= color_dec;
                        if (color_index < 0)
                            color_index = 0;
                    }

                } else if (st->codec.color_table_id & 0x08) {

                    /* if flag bit 3 is set, use the default palette */
                    color_count = 1 << color_depth;
                    if (color_depth == 2)
                        color_table = qt_default_palette_4;
                    else if (color_depth == 4)
                        color_table = qt_default_palette_16;
                    else
                        color_table = qt_default_palette_256;

                    for (j = 0; j < color_count; j++) {
                        r = color_table[j * 4 + 0];
                        g = color_table[j * 4 + 1];
                        b = color_table[j * 4 + 2];
                        c->palette_control.palette[j] =
                            (r << 16) | (g << 8) | (b);
                    }

                } else {

                    /* load the palette from the file */
                    color_start = get_be32(pb);
                    color_count = get_be16(pb);
                    color_end = get_be16(pb);
                    for (j = color_start; j <= color_end; j++) {
                        /* each R, G, or B component is 16 bits;
                         * only use the top 8 bits; skip alpha bytes
                         * up front */
                        get_byte(pb);
                        get_byte(pb);
                        r = get_byte(pb);
                        get_byte(pb);
                        g = get_byte(pb);
                        get_byte(pb);
                        b = get_byte(pb);
                        get_byte(pb);
                        c->palette_control.palette[j] =
                            (r << 16) | (g << 8) | (b);
                    }
                }

                st->codec.palctrl = &c->palette_control;
                st->codec.palctrl->palette_changed = 1;
            } else
                st->codec.palctrl = NULL;

            a.size = size;
	    mov_read_default(c, pb, a);
#endif
	} else {
            st->codec.codec_id = codec_get_id(mov_audio_tags, format);
	    if(st->codec.codec_id==CODEC_ID_AMR_NB || st->codec.codec_id==CODEC_ID_AMR_WB) //from TS26.244
	    {
#ifdef DEBUG
               printf("AMR-NB or AMR-WB audio identified!!\n");
#endif
               get_be32(pb);get_be32(pb); //Reserved_8
               get_be16(pb);//Reserved_2
               get_be16(pb);//Reserved_2
               get_be32(pb);//Reserved_4
               get_be16(pb);//TimeScale
               get_be16(pb);//Reserved_2

                //AMRSpecificBox.(10 bytes)
               
               get_be32(pb); //size
               get_be32(pb); //type=='damr'
               get_be32(pb); //vendor
               get_byte(pb); //decoder version
               get_be16(pb); //mode_set
               get_byte(pb); //mode_change_period
               get_byte(pb); //frames_per_sample

               st->duration = AV_NOPTS_VALUE;//Not possible to get from this info, must count number of AMR frames
               if(st->codec.codec_id==CODEC_ID_AMR_NB)
               {
                   st->codec.sample_rate=8000;
                   st->codec.channels=1;
               }
               else //AMR-WB
               {
                   st->codec.sample_rate=16000;
                   st->codec.channels=1;
               }
               st->codec.bits_per_sample=16;
               st->codec.bit_rate=0; /*It is not possible to tell this before we have 
                                       an audio frame and even then every frame can be different*/
	    }
            else if( st->codec.codec_tag == MKTAG( 'm', 'p', '4', 's' ))
            {
                //This is some stuff for the hint track, lets ignore it!
                //Do some mp4 auto detect.
                c->mp4=1;
                size-=(16);
                url_fskip(pb, size); /* The mp4s atom also contians a esds atom that we can skip*/
            }
	    else if(size>=(16+20))
	    {//16 bytes read, reading atleast 20 more
#ifdef DEBUG
                printf("audio size=0x%X\n",size);
#endif
                uint16_t version = get_be16(pb); /* version */
                get_be16(pb); /* revision level */
                get_be32(pb); /* vendor */

                st->codec.channels = get_be16(pb);		/* channel count */
	        st->codec.bits_per_sample = get_be16(pb);	/* sample size */

                /* handle specific s8 codec */
                get_be16(pb); /* compression id = 0*/
                get_be16(pb); /* packet size = 0 */

                st->codec.sample_rate = ((get_be32(pb) >> 16));
	        //printf("CODECID %d  %d  %.4s\n", st->codec.codec_id, CODEC_ID_PCM_S16BE, (char*)&format);

	        switch (st->codec.codec_id) {
	        case CODEC_ID_PCM_S16BE:
		    if (st->codec.bits_per_sample == 8)
		        st->codec.codec_id = CODEC_ID_PCM_S8;
                    /* fall */
	        case CODEC_ID_PCM_U8:
		    st->codec.bit_rate = st->codec.sample_rate * 8;
		    break;
	        default:
                    ;
	        }

                //Read QT version 1 fields. In version 0 theese dont exist
#ifdef DEBUG
                printf("version =%d mp4=%d\n",version,c->mp4);
                printf("size-(16+20+16)=%d\n",size-(16+20+16));
#endif
                if((version==1) && size>=(16+20+16))
                {
                    get_be32(pb); /* samples per packet */
                    get_be32(pb); /* bytes per packet */
                    get_be32(pb); /* bytes per frame */
                    get_be32(pb); /* bytes per sample */
                    if(size>(16+20+16))
                    {
                        //Optional, additional atom-based fields
#ifdef DEBUG
                        printf("offest=0x%X, sizeleft=%d=0x%x,format=%c%c%c%c\n",(int)url_ftell(pb),size - (16 + 20 + 16 ),size - (16 + 20 + 16 ),
                            (format >> 0) & 0xff,
                            (format >> 8) & 0xff,
                            (format >> 16) & 0xff,
                            (format >> 24) & 0xff);
#endif
                        MOV_atom_t a = { format, url_ftell(pb), size - (16 + 20 + 16 + 8) };
                        mov_read_default(c, pb, a);
                    }
                }
                else
                {
                    //We should be down to 0 bytes here, but lets make sure.
                    size-=(16+20);
#ifdef DEBUG
                    if(size>0)
                        printf("skipping 0x%X bytes\n",size-(16+20));
#endif
                    url_fskip(pb, size);
                }
            }
            else
            {
                size-=16;
                //Unknown size, but lets do our best and skip the rest.
#ifdef DEBUG
                printf("Strange size, skipping 0x%X bytes\n",size);
#endif
                url_fskip(pb, size);
            }
        }
    }

    return 0;
}

static int mov_read_stsc(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    AVStream *st = c->fc->streams[c->fc->nb_streams-1];
    MOVStreamContext *sc = (MOVStreamContext *)st->priv_data;
    int entries, i;

    print_atom("stsc", atom);

    get_byte(pb); /* version */
    get_byte(pb); get_byte(pb); get_byte(pb); /* flags */

    entries = get_be32(pb);
#ifdef DEBUG
printf("track[%i].stsc.entries = %i\n", c->fc->nb_streams-1, entries);
#endif
    sc->sample_to_chunk_sz = entries;
    sc->sample_to_chunk = (MOV_sample_to_chunk_tbl*) av_malloc(entries * sizeof(MOV_sample_to_chunk_tbl));
    if (!sc->sample_to_chunk)
        return -1;
    for(i=0; i<entries; i++) {
        sc->sample_to_chunk[i].first = get_be32(pb);
        sc->sample_to_chunk[i].count = get_be32(pb);
        sc->sample_to_chunk[i].id = get_be32(pb);
#ifdef DEBUG
/*        printf("sample_to_chunk first=%ld count=%ld, id=%ld\n", sc->sample_to_chunk[i].first, sc->sample_to_chunk[i].count, sc->sample_to_chunk[i].id); */
#endif
    }
    return 0;
}

static int mov_read_stsz(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    AVStream *st = c->fc->streams[c->fc->nb_streams-1];
    MOVStreamContext *sc = (MOVStreamContext *)st->priv_data;
    int entries, i;

    print_atom("stsz", atom);

    get_byte(pb); /* version */
    get_byte(pb); get_byte(pb); get_byte(pb); /* flags */

    sc->sample_size = get_be32(pb);
    entries = get_be32(pb);
    sc->sample_count = entries;
#ifdef DEBUG
    printf("sample_size = %ld sample_count = %ld\n", sc->sample_size, sc->sample_count);
#endif
    if(sc->sample_size)
        return 0; /* there isn't any table following */
    sc->sample_sizes = (long*) av_malloc(entries * sizeof(long));
    if (!sc->sample_sizes)
        return -1;
    for(i=0; i<entries; i++) {
        sc->sample_sizes[i] = get_be32(pb);
#ifdef DEBUG
/*        printf("sample_sizes[]=%ld\n", sc->sample_sizes[i]); */
#endif
    }
    return 0;
}

static int mov_read_stts(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    AVStream *st = c->fc->streams[c->fc->nb_streams-1];
    //MOVStreamContext *sc = (MOVStreamContext *)st->priv_data;
    int entries, i;
    int duration=0;
    int total_sample_count=0;

    print_atom("stts", atom);

    get_byte(pb); /* version */
    get_byte(pb); get_byte(pb); get_byte(pb); /* flags */
    entries = get_be32(pb);


#ifdef DEBUG
printf("track[%i].stts.entries = %i\n", c->fc->nb_streams-1, entries);
#endif
    for(i=0; i<entries; i++) {
        int sample_duration;
        int sample_count;

        sample_count=get_be32(pb);
        sample_duration = get_be32(pb);
#ifdef DEBUG
        printf("sample_count=%d, sample_duration=%d\n",sample_count,sample_duration);
#endif
        duration+=sample_duration*sample_count;
        total_sample_count+=sample_count;

#if 0 //We calculate an average instead, needed by .mp4-files created with nec e606 3g phone

        if (!i && st->codec.codec_type==CODEC_TYPE_VIDEO) {
            st->codec.frame_rate_base = sample_duration ? sample_duration : 1;
            st->codec.frame_rate = c->streams[c->total_streams]->time_scale;
#ifdef DEBUG
            printf("VIDEO FRAME RATE= %i (sd= %i)\n", st->codec.frame_rate, sample_duration);
#endif
        }
#endif
    }

#define MAX(a,b) a>b?a:b
#define MIN(a,b) a>b?b:a
    /*The stsd atom which contain codec type sometimes comes after the stts so we cannot check for codec_type*/
    if(duration>0)
    {
        //Find greatest common divisor to avoid overflow using the Euclidean Algorithm...
        uint32_t max=MAX(duration,total_sample_count);
        uint32_t min=MIN(duration,total_sample_count);
        uint32_t spare=max%min;

        while(spare!=0)
        {
            max=min;
            min=spare;
            spare=max%min;
        }
        
        duration/=min;
        total_sample_count/=min;

        //Only support constant frame rate. But lets calculate the average. Needed by .mp4-files created with nec e606 3g phone.
        //To get better precision, we use the duration as frame_rate_base

        st->codec.frame_rate_base=duration;
        st->codec.frame_rate = c->streams[c->total_streams]->time_scale * total_sample_count;

#ifdef DEBUG
        printf("FRAME RATE average (video or audio)= %f (tot sample count= %i ,tot dur= %i timescale=%d)\n", (float)st->codec.frame_rate/st->codec.frame_rate_base,total_sample_count,duration,c->streams[c->total_streams]->time_scale);
#endif
    }
    else
    {
        st->codec.frame_rate_base = 1;
        st->codec.frame_rate = c->streams[c->total_streams]->time_scale;
    }
#undef MAX
#undef MIN
    return 0;
}

static int mov_read_trak(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    AVStream *st;
    MOVStreamContext *sc;

    print_atom("trak", atom);

    st = av_new_stream(c->fc, c->fc->nb_streams);
    if (!st) return -2;
    sc = (MOVStreamContext*) av_mallocz(sizeof(MOVStreamContext));
    if (!sc) {
	av_free(st);
        return -1;
    }

    sc->sample_to_chunk_index = -1;
    st->priv_data = sc;
    st->codec.codec_type = CODEC_TYPE_MOV_OTHER;
    st->start_time = 0; /* XXX: check */
    st->duration = (c->duration * (int64_t)AV_TIME_BASE) / c->time_scale;
    c->streams[c->fc->nb_streams-1] = sc;

    return mov_read_default(c, pb, atom);
}

static int mov_read_tkhd(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    AVStream *st;

    print_atom("tkhd", atom);

    st = c->fc->streams[c->fc->nb_streams-1];

    get_byte(pb); /* version */

    get_byte(pb); get_byte(pb);
    get_byte(pb); /* flags */
    /*
    MOV_TRACK_ENABLED 0x0001
    MOV_TRACK_IN_MOVIE 0x0002
    MOV_TRACK_IN_PREVIEW 0x0004
    MOV_TRACK_IN_POSTER 0x0008
    */

    get_be32(pb); /* creation time */
    get_be32(pb); /* modification time */
    st->id = (int)get_be32(pb); /* track id (NOT 0 !)*/
    get_be32(pb); /* reserved */
    st->start_time = 0; /* check */
    st->duration = (get_be32(pb) * (int64_t)AV_TIME_BASE) / c->time_scale; /* duration */
    get_be32(pb); /* reserved */
    get_be32(pb); /* reserved */

    get_be16(pb); /* layer */
    get_be16(pb); /* alternate group */
    get_be16(pb); /* volume */
    get_be16(pb); /* reserved */

    url_fskip(pb, 36); /* display matrix */

    /* those are fixed-point */
    st->codec.width = get_be32(pb) >> 16; /* track width */
    st->codec.height = get_be32(pb) >> 16; /* track height */

    return 0;
}

/* this atom should be null (from specs), but some buggy files put the 'moov' atom inside it... */
/* like the files created with Adobe Premiere 5.0, for samples see */
/* http://graphics.tudelft.nl/~wouter/publications/soundtests/ */
static int mov_read_wide(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    int err;

#ifdef DEBUG
    print_atom("wide", atom);
    debug_indent++;
#endif
    if (atom.size < 8)
        return 0; /* continue */
    if (get_be32(pb) != 0) { /* 0 sized mdat atom... use the 'wide' atom size */
        url_fskip(pb, atom.size - 4);
        return 0;
    }
    atom.type = get_le32(pb);
    atom.offset += 8;
    atom.size -= 8;
    if (atom.type != MKTAG('m', 'd', 'a', 't')) {
        url_fskip(pb, atom.size);
        return 0;
    }
    err = mov_read_mdat(c, pb, atom);
#ifdef DEBUG
    debug_indent--;
#endif
    return err;
}


#ifdef CONFIG_ZLIB
static int null_read_packet(void *opaque, uint8_t *buf, int buf_size)
{
    return -1;
}

static int mov_read_cmov(MOVContext *c, ByteIOContext *pb, MOV_atom_t atom)
{
    ByteIOContext ctx;
    uint8_t *cmov_data;
    uint8_t *moov_data; /* uncompressed data */