Function smc_encode_stream

libavcodec/smcenc.c:115–516

     s->color_octets[i][7] == distinct_values[x])

static void smc_encode_stream(SMCContext *s, const AVFrame *frame,
                              PutByteContext *pb)
{
    const uint8_t *src_pixels = (const uint8_t *)frame->data[0];
    const ptrdiff_t stride = frame->linesize[0];
    const uint8_t *prev_pixels = (const uint8_t *)s->prev_frame->data[0];
    const ptrdiff_t prev_stride = s->prev_frame->linesize[0];
    uint8_t *distinct_values = s->distinct_values;
    const uint8_t *pixel_ptr, *row_ptr;
    const int height = frame->height;
    const int width = frame->width;
    int block_counter = 0;
    int color_pair_index = 0;
    int color_quad_index = 0;
    int color_octet_index = 0;
    int color_table_index;  /* indexes to color pair, quad, or octet tables */
    int total_blocks;
    int cur_y = 0;
    int cur_x = 0;

    /* Number of 4x4 blocks in frame. */
    total_blocks = ((width + 3) / 4) * ((height + 3) / 4);

    pixel_ptr = row_ptr = src_pixels;

    while (block_counter < total_blocks) {
        const uint8_t *xpixel_ptr = pixel_ptr;
        const uint8_t *xrow_ptr = row_ptr;
        int intra_skip_blocks = 0;
        int inter_skip_blocks = 0;
        int coded_distinct = 0;
        int coded_blocks = 0;
        int cache_index;
        int distinct = 0;
        int blocks = 0;
        int frame_y = cur_y;
        int frame_x = cur_x;

        while (prev_pixels && s->key_frame == 0 && block_counter + inter_skip_blocks < total_blocks) {
            const int y_size = FFMIN(4, height - cur_y);
            const int x_size = FFMIN(4, width  - cur_x);
            int compare = 0;

            for (int y = 0; y < y_size; y++) {
                const uint8_t *prev_pixel_ptr = prev_pixels + (y + cur_y) * prev_stride + cur_x;

                compare |= !!memcmp(prev_pixel_ptr, pixel_ptr + y * stride, x_size);
                if (compare)
                    break;
            }

            if (compare)
                break;

            inter_skip_blocks++;
            if (inter_skip_blocks >= 256)
                break;