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  • /*
     * qt-faststart.c, v0.1
     * by Mike Melanson (melanson@pcisys.net)
     * This file is placed in the public domain. Use the program however you
     * see fit.
     *
     * This utility rearranges a Quicktime file such that the moov atom
     * is in front of the data, thus facilitating network streaming.
     *
     * Compile this program using:
     *  cc qt-faststart.c -o qt-faststart
     * Invoke the program with:
     *  qt-faststart <infile.mov> <outfile.mov>
     *
     * Notes: Quicktime files can come in many configurations of top-level
     * atoms. This utility stipulates that the very last atom in the file needs
     * to be a moov atom. When given such a file, this utility will rearrange
     * the top-level atoms by shifting the moov atom from the back of the file
     * to the front, and patch the chunk offsets along the way. This utility
     * presently only operates on uncompressed moov atoms.
     */
    
    #include <stdio.h>
    #include <stdlib.h>
    #include <inttypes.h>
    
    #define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
    #define BE_32(x) ((((uint8_t*)(x))[0] << 24) | \
                      (((uint8_t*)(x))[1] << 16) | \
                      (((uint8_t*)(x))[2] << 8) | \
                       ((uint8_t*)(x))[3])
    #define BE_64(x) (((uint64_t)(((uint8_t*)(x))[0]) << 56) | \
                      ((uint64_t)(((uint8_t*)(x))[1]) << 48) | \
                      ((uint64_t)(((uint8_t*)(x))[2]) << 40) | \
                      ((uint64_t)(((uint8_t*)(x))[3]) << 32) | \
                      ((uint64_t)(((uint8_t*)(x))[4]) << 24) | \
                      ((uint64_t)(((uint8_t*)(x))[5]) << 16) | \
                      ((uint64_t)(((uint8_t*)(x))[6]) << 8) | \
                      ((uint64_t)((uint8_t*)(x))[7]))
    
    #define BE_FOURCC( ch0, ch1, ch2, ch3 )             \
            ( (uint32_t)(unsigned char)(ch3) |          \
            ( (uint32_t)(unsigned char)(ch2) << 8 ) |   \
            ( (uint32_t)(unsigned char)(ch1) << 16 ) |  \
            ( (uint32_t)(unsigned char)(ch0) << 24 ) )
    
    #define QT_ATOM BE_FOURCC
    /* top level atoms */
    #define FREE_ATOM QT_ATOM('f', 'r', 'e', 'e')
    #define JUNK_ATOM QT_ATOM('j', 'u', 'n', 'k')
    #define MDAT_ATOM QT_ATOM('m', 'd', 'a', 't')
    #define MOOV_ATOM QT_ATOM('m', 'o', 'o', 'v')
    #define PNOT_ATOM QT_ATOM('p', 'n', 'o', 't')
    #define SKIP_ATOM QT_ATOM('s', 'k', 'i', 'p')
    #define WIDE_ATOM QT_ATOM('w', 'i', 'd', 'e')
    #define PICT_ATOM QT_ATOM('P', 'I', 'C', 'T')
    #define FTYP_ATOM QT_ATOM('f', 't', 'y', 'p')
    
    #define CMOV_ATOM QT_ATOM('c', 'm', 'o', 'v')
    #define STCO_ATOM QT_ATOM('s', 't', 'c', 'o')
    #define CO64_ATOM QT_ATOM('c', 'o', '6', '4')
    
    #define ATOM_PREAMBLE_SIZE 8
    #define COPY_BUFFER_SIZE 1024
    
    int main(int argc, char *argv[])
    {
        FILE *infile;
        FILE *outfile;
        unsigned char atom_bytes[ATOM_PREAMBLE_SIZE];
        uint32_t atom_type = 0;
    
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        uint64_t atom_size = 0;
    
        uint64_t last_offset;
        unsigned char *moov_atom;
    
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        unsigned char *ftyp_atom = 0;
    
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        uint64_t ftyp_atom_size = 0;
    
        uint64_t i, j;
        uint32_t offset_count;
        uint64_t current_offset;
    
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        uint64_t start_offset = 0;
    
        unsigned char copy_buffer[COPY_BUFFER_SIZE];
        int bytes_to_copy;
    
        if (argc != 3) {
            printf ("Usage: qt-faststart <infile.mov> <outfile.mov>\n");
            return 0;
        }
    
        infile = fopen(argv[1], "rb");
        if (!infile) {
            perror(argv[1]);
            return 1;
        }
    
        /* traverse through the atoms in the file to make sure that 'moov' is
         * at the end */
        while (!feof(infile)) {
            if (fread(atom_bytes, ATOM_PREAMBLE_SIZE, 1, infile) != 1) {
                break;
            }
    
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            atom_size = (uint32_t)BE_32(&atom_bytes[0]);
    
            atom_type = BE_32(&atom_bytes[4]);
    
            if ((atom_type != FREE_ATOM) &&
                (atom_type != JUNK_ATOM) &&
                (atom_type != MDAT_ATOM) &&
                (atom_type != MOOV_ATOM) &&
                (atom_type != PNOT_ATOM) &&
                (atom_type != SKIP_ATOM) &&
                (atom_type != WIDE_ATOM) &&
                (atom_type != PICT_ATOM) &&
                (atom_type != FTYP_ATOM)) {
                printf ("encountered non-QT top-level atom (is this a Quicktime file?)\n");
                break;
            }
    
    
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            /* keep ftyp atom */
            if (atom_type == FTYP_ATOM) {
                ftyp_atom_size = atom_size;
                ftyp_atom = malloc(ftyp_atom_size);
                if (!ftyp_atom) {
                    printf ("could not allocate 0x%llX byte for ftyp atom\n",
                            atom_size);
                    fclose(infile);
                    return 1;
                }
                fseeko(infile, -ATOM_PREAMBLE_SIZE, SEEK_CUR);
                if (fread(ftyp_atom, atom_size, 1, infile) != 1) {
                    perror(argv[1]);
                    free(ftyp_atom);
                    fclose(infile);
                    return 1;
                }
                start_offset = ftello(infile);
                continue;
            }
    
    
            /* 64-bit special case */
            if (atom_size == 1) {
                if (fread(atom_bytes, ATOM_PREAMBLE_SIZE, 1, infile) != 1) {
                    break;
                }
                atom_size = BE_64(&atom_bytes[0]);
    
                fseeko(infile, atom_size - ATOM_PREAMBLE_SIZE * 2, SEEK_CUR);
    
                fseeko(infile, atom_size - ATOM_PREAMBLE_SIZE, SEEK_CUR);
    
            }
        }
    
        if (atom_type != MOOV_ATOM) {
            printf ("last atom in file was not a moov atom\n");
            fclose(infile);
            return 0;
        }
    
        /* moov atom was, in fact, the last atom in the chunk; load the whole
         * moov atom */
    
        fseeko(infile, -atom_size, SEEK_END);
        last_offset = ftello(infile);
    
        moov_atom_size = atom_size;
        moov_atom = malloc(moov_atom_size);
        if (!moov_atom) {
            printf ("could not allocate 0x%llX byte for moov atom\n",
                atom_size);
            fclose(infile);
            return 1;
        }
        if (fread(moov_atom, atom_size, 1, infile) != 1) {
            perror(argv[1]);
            free(moov_atom);
            fclose(infile);
            return 1;
        }
    
        /* this utility does not support compressed atoms yet, so disqualify
         * files with compressed QT atoms */
        if (BE_32(&moov_atom[12]) == CMOV_ATOM) {
            printf ("this utility does not support compressed moov atoms yet\n");
            free(moov_atom);
            fclose(infile);
            return 1;
        }
    
        /* close; will be re-opened later */
        fclose(infile);
    
        /* crawl through the moov chunk in search of stco or co64 atoms */
        for (i = 4; i < moov_atom_size - 4; i++) {
            atom_type = BE_32(&moov_atom[i]);
            if (atom_type == STCO_ATOM) {
                printf (" patching stco atom...\n");
                atom_size = BE_32(&moov_atom[i - 4]);
                if (i + atom_size - 4 > moov_atom_size) {
                    printf (" bad atom size\n");
                    free(moov_atom);
                    return 1;
                }
                offset_count = BE_32(&moov_atom[i + 8]);
                for (j = 0; j < offset_count; j++) {
                    current_offset = BE_32(&moov_atom[i + 12 + j * 4]);
                    current_offset += moov_atom_size;
                    moov_atom[i + 12 + j * 4 + 0] = (current_offset >> 24) & 0xFF;
                    moov_atom[i + 12 + j * 4 + 1] = (current_offset >> 16) & 0xFF;
                    moov_atom[i + 12 + j * 4 + 2] = (current_offset >>  8) & 0xFF;
                    moov_atom[i + 12 + j * 4 + 3] = (current_offset >>  0) & 0xFF;
                }
                i += atom_size - 4;
            } else if (atom_type == CO64_ATOM) {
                printf (" patching co64 atom...\n");
                atom_size = BE_32(&moov_atom[i - 4]);
                if (i + atom_size - 4 > moov_atom_size) {
                    printf (" bad atom size\n");
                    free(moov_atom);
                    return 1;
                }
                offset_count = BE_32(&moov_atom[i + 8]);
                for (j = 0; j < offset_count; j++) {
                    current_offset = BE_64(&moov_atom[i + 12 + j * 8]);
                    current_offset += moov_atom_size;
                    moov_atom[i + 12 + j * 8 + 0] = (current_offset >> 56) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 1] = (current_offset >> 48) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 2] = (current_offset >> 40) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 3] = (current_offset >> 32) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 4] = (current_offset >> 24) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 5] = (current_offset >> 16) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 6] = (current_offset >>  8) & 0xFF;
                    moov_atom[i + 12 + j * 8 + 7] = (current_offset >>  0) & 0xFF;
                }
                i += atom_size - 4;
            }
        }
    
        /* re-open the input file and open the output file */
        infile = fopen(argv[1], "rb");
        if (!infile) {
            perror(argv[1]);
            free(moov_atom);
            return 1;
        }
    
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        /* seek after ftyp atom if needed */
        fseeko(infile, start_offset, SEEK_SET);
    
    
        outfile = fopen(argv[2], "wb");
        if (!outfile) {
            perror(argv[2]);
            fclose(outfile);
            free(moov_atom);
            return 1;
        }
    
    
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        /* dump the same ftyp atom */
        if (ftyp_atom_size > 0) {
            printf (" writing ftyp atom...\n");
            if (fwrite(ftyp_atom, ftyp_atom_size, 1, outfile) != 1) {
                perror(argv[2]);
                goto error_out;
            }
        }
    
    
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        printf (" writing moov atom...\n");
    
        if (fwrite(moov_atom, moov_atom_size, 1, outfile) != 1) {
            perror(argv[2]);
            goto error_out;
        }
    
        /* copy the remainder of the infile, from offset 0 -> last_offset - 1 */
        printf (" copying rest of file...\n");
        while (last_offset) {
            if (last_offset > COPY_BUFFER_SIZE)
                bytes_to_copy = COPY_BUFFER_SIZE;
            else
                bytes_to_copy = last_offset;
    
            if (fread(copy_buffer, bytes_to_copy, 1, infile) != 1) {
                perror(argv[1]);
                goto error_out;
            }
            if (fwrite(copy_buffer, bytes_to_copy, 1, outfile) != 1) {
                perror(argv[2]);
                goto error_out;
            }
    
            last_offset -= bytes_to_copy;
        }
    
        fclose(infile);
        fclose(outfile);
        free(moov_atom);
    
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        if (ftyp_atom_size > 0)
            free(ftyp_atom);
    
    
        return 0;
    
    error_out:
        fclose(infile);
        fclose(outfile);
        free(moov_atom);
    
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        if (ftyp_atom_size > 0)
            free(ftyp_atom);