static int execute_code(AVCodecContext * avctx, int c)

{

    AnsiContext *s = avctx->priv_data;

    int ret, i, width, height;

    switch(c) {

    case 'A': //Cursor Up

        s->y = FFMAX(s->y - (s->nb_args > 0 ? s->args[0]*s->font_height : s->font_height), 0);

        break;

    case 'B': //Cursor Down

        s->y = FFMIN(s->y + (s->nb_args > 0 ? s->args[0]*s->font_height : s->font_height), avctx->height - s->font_height);

        break;

    case 'C': //Cursor Right

        s->x = FFMIN(s->x + (s->nb_args > 0 ? s->args[0]*FONT_WIDTH : FONT_WIDTH), avctx->width  - FONT_WIDTH);

        break;

    case 'D': //Cursor Left

        s->x = FFMAX(s->x - (s->nb_args > 0 ? s->args[0]*FONT_WIDTH : FONT_WIDTH), 0);

        break;

    case 'H': //Cursor Position

    case 'f': //Horizontal and Vertical Position

        s->y = s->nb_args > 0 ? av_clip((s->args[0] - 1)*s->font_height, 0, avctx->height - s->font_height) : 0;

        s->x = s->nb_args > 1 ? av_clip((s->args[1] - 1)*FONT_WIDTH,     0, avctx->width  - FONT_WIDTH) : 0;

        break;

    case 'h': //set creen mode

    case 'l': //reset screen mode

        if (s->nb_args < 2)

            s->args[0] = DEFAULT_SCREEN_MODE;

        width = avctx->width;

        height = avctx->height;

        switch(s->args[0]) {

        case 0: case 1: case 4: case 5: case 13: case 19: //320x200 (25 rows)

            s->font = avpriv_cga_font;

            s->font_height = 8;

            width  = 40<<3;

            height = 25<<3;

            break;

        case 2: case 3: //640x400 (25 rows)

            s->font = avpriv_vga16_font;

            s->font_height = 16;

            width  = 80<<3;

            height = 25<<4;

            break;

        case 6: case 14: //640x200 (25 rows)

            s->font = avpriv_cga_font;

            s->font_height = 8;

            width  = 80<<3;

            height = 25<<3;

            break;

        case 7: //set line wrapping

            break;

        case 15: case 16: //640x350 (43 rows)

            s->font = avpriv_cga_font;

            s->font_height = 8;

            width  = 80<<3;

            height = 43<<3;

            break;

        case 17: case 18: //640x480 (60 rows)

            s->font = avpriv_cga_font;

            s->font_height = 8;

            width  = 80<<3;

            height = 60<<4;

            break;

        default:

            av_log_ask_for_sample(avctx, "unsupported screen mode\n");

        }

        if (width != avctx->width || height != avctx->height) {

            if (s->frame.data[0])

                avctx->release_buffer(avctx, &s->frame);

            avcodec_set_dimensions(avctx, width, height);

            ret = avctx->get_buffer(avctx, &s->frame);

            if (ret < 0) {

                av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");

                return ret;

            }

            s->frame.pict_type           = AV_PICTURE_TYPE_I;

            s->frame.palette_has_changed = 1;

            set_palette((uint32_t *)s->frame.data[1]);

            erase_screen(avctx);

        } else if (c == 'l') {

            erase_screen(avctx);

        }

        break;

    case 'J': //Erase in Page

        switch (s->args[0]) {

        case 0:

            erase_line(avctx, s->x, avctx->width - s->x);

            if (s->y < avctx->height - s->font_height)

                memset(s->frame.data[0] + (s->y + s->font_height)*s->frame.linesize[0],

                    DEFAULT_BG_COLOR, (avctx->height - s->y - s->font_height)*s->frame.linesize[0]);

            break;

        case 1:

            erase_line(avctx, 0, s->x);

            if (s->y > 0)

                memset(s->frame.data[0], DEFAULT_BG_COLOR, s->y * s->frame.linesize[0]);

            break;

        case 2:

            erase_screen(avctx);

        }

        break;

    case 'K': //Erase in Line

        switch(s->args[0]) {

        case 0:

            erase_line(avctx, s->x, avctx->width - s->x);

            break;

        case 1:

            erase_line(avctx, 0, s->x);

            break;

        case 2:

            erase_line(avctx, 0, avctx->width);

        }

        break;

    case 'm': //Select Graphics Rendition

        if (s->nb_args == 0) {

            s->nb_args = 1;

            s->args[0] = 0;

        }

        for (i = 0; i < FFMIN(s->nb_args, MAX_NB_ARGS); i++) {

            int m = s->args[i];

            if (m == 0) {

                s->attributes = 0;

                s->fg = DEFAULT_FG_COLOR;

                s->bg = DEFAULT_BG_COLOR;

            } else if (m == 1 || m == 2 || m == 4 || m == 5 || m == 7 || m == 8) {

                s->attributes |= 1 << (m - 1);

            } else if (m >= 30 && m <= 37) {

                s->fg = ansi_to_cga[m - 30];

            } else if (m == 38 && i + 2 < s->nb_args && s->args[i + 1] == 5 && s->args[i + 2] < 256) {

                int index = s->args[i + 2];

                s->fg = index < 16 ? ansi_to_cga[index] : index;

                i += 2;

            } else if (m == 39) {

                s->fg = ansi_to_cga[DEFAULT_FG_COLOR];

            } else if (m >= 40 && m <= 47) {

                s->bg = ansi_to_cga[m - 40];

            } else if (m == 48 && i + 2 < s->nb_args && s->args[i + 1] == 5 && s->args[i + 2] < 256) {

                int index = s->args[i + 2];

                s->bg = index < 16 ? ansi_to_cga[index] : index;

                i += 2;

            } else if (m == 49) {

                s->fg = ansi_to_cga[DEFAULT_BG_COLOR];

            } else {

                av_log_ask_for_sample(avctx, "unsupported rendition parameter\n");

            }

        }

        break;

    case 'n': //Device Status Report

    case 'R': //report current line and column

        /* ignore */

        break;

    case 's': //Save Cursor Position

        s->sx = s->x;

        s->sy = s->y;

        break;

    case 'u': //Restore Cursor Position

        s->x = av_clip(s->sx, 0, avctx->width  - FONT_WIDTH);

        s->y = av_clip(s->sy, 0, avctx->height - s->font_height);

        break;

    default:

        av_log_ask_for_sample(avctx, "unsupported escape code\n");

        break;

    }

    return 0;

}
