diff options
Diffstat (limited to 'libmpcodecs/vd_msrle.c')
| -rw-r--r-- | libmpcodecs/vd_msrle.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/libmpcodecs/vd_msrle.c b/libmpcodecs/vd_msrle.c new file mode 100644 index 0000000000..2ef0c9305a --- /dev/null +++ b/libmpcodecs/vd_msrle.c @@ -0,0 +1,188 @@ +#include <stdio.h> +#include <stdlib.h> + +#include "config.h" +#include "mp_msg.h" + +#include "vd_internal.h" + +static vd_info_t info = { + "Microsoft RLE decoder", + "msrle", + VFM_MSRLE, + "A'rpi", + "Mike Melanson", + "native codec" +}; + +LIBVD_EXTERN(msrle) + +// to set/get/query special features/parameters +static int control(sh_video_t *sh,int cmd,void* arg,...){ + return CONTROL_UNKNOWN; +} + +// init driver +static int init(sh_video_t *sh){ + return mpcodecs_config_vo(sh,sh->disp_w,sh->disp_h,IMGFMT_BGR24); +} + +// uninit driver +static void uninit(sh_video_t *sh){ +} + +//mp_image_t* mpcodecs_get_image(sh_video_t *sh, int mp_imgtype, int mp_imgflag, int w, int h); + +#define FETCH_NEXT_STREAM_BYTE() \ + if (stream_ptr >= encoded_size) \ + { \ + mp_msg(MSGT_DECVIDEO, MSGL_WARN, \ + "MS RLE: stream ptr just went out of bounds (1)\n"); \ + return; \ + } \ + stream_byte = encoded[stream_ptr++]; + + +void decode_msrle8( + unsigned char *encoded, + int encoded_size, + unsigned char *decoded, + int width, + int height, + unsigned char *palette_map, + int bytes_per_pixel) +{ + unsigned char r, g, b; + int stream_ptr = 0; + unsigned char rle_code; + unsigned char extra_byte; + unsigned char stream_byte; + int frame_size = width * height * bytes_per_pixel; + int pixel_ptr = 0; + int row_dec = width * bytes_per_pixel; + int row_ptr = (height - 1) * row_dec; + +/* +static int counter = 0; +int i; +printf ("run %d: ", counter++); +for (i = 0; i < 16; i++) + printf (" %02X", encoded[i]); +printf ("\n"); +for (i = encoded_size - 16; i < encoded_size; i++) + printf (" (%d)%02X", i, encoded[i]); +printf ("\n"); +*/ + + while (row_ptr >= 0) + { + FETCH_NEXT_STREAM_BYTE(); + rle_code = stream_byte; + if (rle_code == 0) + { + // fetch the next byte to see how to handle escape code + FETCH_NEXT_STREAM_BYTE(); + if (stream_byte == 0) + { + // line is done, goto the next one + row_ptr -= row_dec; + pixel_ptr = 0; + } + else if (stream_byte == 1) + // decode is done + return; + else if (stream_byte == 2) + { + // reposition frame decode coordinates + FETCH_NEXT_STREAM_BYTE(); + pixel_ptr += stream_byte * bytes_per_pixel; + FETCH_NEXT_STREAM_BYTE(); + row_ptr -= stream_byte * row_dec; + } + else + { + // copy pixels from encoded stream + if ((row_ptr + pixel_ptr + stream_byte * bytes_per_pixel > frame_size) || + (row_ptr < 0)) + { + mp_msg(MSGT_DECVIDEO, MSGL_WARN, + "MS RLE: frame ptr just went out of bounds (1)\n"); + return; + } + + rle_code = stream_byte; + extra_byte = stream_byte & 0x01; + if (stream_ptr + rle_code + extra_byte > encoded_size) + { + mp_msg(MSGT_DECVIDEO, MSGL_WARN, + "MS RLE: stream ptr just went out of bounds (2)\n"); + return; + } + + while (rle_code--) + { + r = palette_map[encoded[stream_ptr] * 4 + 2]; + g = palette_map[encoded[stream_ptr] * 4 + 1]; + b = palette_map[encoded[stream_ptr] * 4 + 0]; + stream_ptr++; + decoded[row_ptr + pixel_ptr + 0] = b; + decoded[row_ptr + pixel_ptr + 1] = g; + decoded[row_ptr + pixel_ptr + 2] = r; + pixel_ptr += bytes_per_pixel; + } + + // if the RLE code is odd, skip a byte in the stream + if (extra_byte) + stream_ptr++; + } + } + else + { + // decode a run of data + if ((row_ptr + pixel_ptr + stream_byte * bytes_per_pixel > frame_size) || + (row_ptr < 0)) + { + mp_msg(MSGT_DECVIDEO, MSGL_WARN, + "MS RLE: frame ptr just went out of bounds (2)\n"); + return; + } + + FETCH_NEXT_STREAM_BYTE(); + + r = palette_map[stream_byte * 4 + 2]; + g = palette_map[stream_byte * 4 + 1]; + b = palette_map[stream_byte * 4 + 0]; + while(rle_code--) + { + decoded[row_ptr + pixel_ptr + 0] = b; + decoded[row_ptr + pixel_ptr + 1] = g; + decoded[row_ptr + pixel_ptr + 2] = r; + pixel_ptr += bytes_per_pixel; + } + } + } + + // one last sanity check on the way out + if (stream_ptr < encoded_size) + mp_msg(MSGT_DECVIDEO, MSGL_WARN, + "MS RLE: ended frame decode with bytes left over (%d < %d)\n", + stream_ptr, encoded_size); +} + +// decode a frame +static mp_image_t* decode(sh_video_t *sh,void* data,int len,int flags){ + mp_image_t* mpi; + if(len<=0) return NULL; // skipped frame + + mpi=mpcodecs_get_image(sh, MP_IMGTYPE_STATIC, MP_IMGFLAG_PRESERVE, + sh->disp_w, sh->disp_h); + if(!mpi) return NULL; + + decode_msrle8( + data,len, mpi->planes[0], + sh->disp_w, sh->disp_h, + (unsigned char *)sh->bih+40, + mpi->bpp/8); + + return mpi; +} |