Codec45 is used in some RA2 videos on top of codec37. It consists of 2 tables (768 and 32768 bytes), and datapackets like codec2 (delta-x, delta-y) with a pixel counter instead of a color value. It then reads the 4 surrounding pixels, looks up 3 separate values for each in table1, adds them together to form an index into table2 for a new pixel value, in a row. The data coming in gets the x/y coordinates out of the visible area very quickly (2-3 iterations); I don't see any visual difference between the ffmpeg-produced frames and ones captured with dosbox from rebel assault 2, which leads me to believe this codec never worked as intended.
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| @@ -1673,6 +1673,8 @@ static int process_frame_obj(SANMVideoContext *ctx, GetByteContext *gb) · 1672 unmodified lines | |||
| 1673 | return old_codec23(ctx, gb, top, left, w, h, param, parm2); | 1673 | return old_codec23(ctx, gb, top, left, w, h, param, parm2); |
| 1674 | case 37: | 1674 | case 37: |
| 1675 | return old_codec37(ctx, w, h); | 1675 | return old_codec37(ctx, w, h); |
| 1676 | case 45: | ||
| 1677 | return 0; | ||
| 1676 | case 47: | 1678 | case 47: |
| 1677 | return old_codec47(ctx, w, h); | 1679 | return old_codec47(ctx, w, h); |
| 1678 | case 48: | 1680 | case 48: |