changes.decoder

MPEG-2 has 7 distinct parts as well. The first part is the Systems section which defines the contain

94/07/04 public release of version 1.1a
=======================================

94/07/04 sE

display.c:
- renamed shminfo to shminfo1 (name clash ?)

94/07/01 sE

getblk.c:
- fixed a bug in MPEG-1 escape decoding where it was assumed that char would
  always be signed

94/06/30 public release of version 1.1
======================================

94/06/28 sE

getpic.c:
- correct filename in comment
- framenum is no longer a static variable but a parameter passed from main()

global.h:
- correct filename in comment
- updated protoypes
- added missing protoype for display_second_field
- removed unsused T_NONE

idct.c:
- removed short-circuit for even-coefficient-only case

mpeg2dec.c:
- removed picture variable in main()
- added framenum
- changed an #if to #ifdef

94/06/26 sE

display.c:
- moved display window position from (200,300) to (200,200)
- added higher quality interlaced to progressive conversion
  (dithertop420(), ditherbot420())
- fixed a dithering bug in ditherbot()

getblk.c:
- added missing saturation of MPEG-1 reconstructed coefficients
  to  -2048..2047

getvlc.c:
- printbits() moved to mpeg2dec.c
- fixed some warnings which went to stdout instead of stderr

motion.c:
- fixed an incorrect trace printf format string

mpeg2dec.c:
- some modifications for hiQdither
- no longer requires outfile parameter for X11 display
- added printbits()


94/06/19 sE

made convmat[] global (is used by both store.c and display.c)

display.c:
- 4:4:4 support

mpeg2dec.c:
- added -t (trace) and -q (quiet) flags

store.c:
- collapsed store_tga() and store_ppm() into one routine
- added 4:2:2 and 4:4:4 support for .tga and .ppm
- error message if store_sif() is used with 4:4:4 data
- 'saving ...' messages now depend on quiet instead of verbose
- removed unused putlong()

94/06/16 sE  cummulative changes since version 1.0

changed all long variables to int
added X11 output (display.c)
added 4:2:2 and 4:4:4 support
added low level tracing

getblk.c:
- expressions of the form &(bool ? ptr0 : ptr1)[idx] confused
  some compilers, changed to if statements

gethdr.c:
- chroma_format is no longer ignored
- support for chroma quantization matrices (instead of ignoring them)
  (needed for 4:2:2 and 4:4:4)

getpic.c:
- several modifications for 4:2:2 and 4:4:4

getvlc.h:
- added cbp code for 0 (needed for 4:2:2 and 4:4:4)

idct.c:
- reduced accuracy of the idct coefficients by one bit to fix
  a potential overflow problem (still meets IEEE1180)
- intermediate storage is now short and in-place
- some speed-ups

recon.c:
- fixed bug in prediction of spatial scalable field pictures (did not
  always take spatial_temporal_weight into account)

spatscal.c:
- use one field aperture filter for field pictures (changed from CD to DIS)

store.c:
- better chrominance upsampling filters (Aeyung Cheung)



94/05/17 public release of version 1.0
======================================

94/05/16 sE

style changes, some comments

store.c:
- indexing bug in conv420to422 fixed


94/05/12 sE

name changed to mpeg2decode

store.c:
 - conv422to444 and conv420to422 now convert one component per call, not both
   at the same time
 - changed upsampling filters to be based on those proposed by Cheung
 - added filter for MPEG-1 4:2:2 to 4:4:4 upsampling


94/05/11 sE

global.h:
- updated all prototypes

getpict.c:
- fixed bug in No_MC predicted macroblocks in P-field pictures; motion_type
  and mv_field_sel are now set to correct values
- changed name of DC coef. predictors to dc_dct_pred[3] and made them
  local to getMBs, they are now passed as parameters to getintrablock()
  and getmpg2intrablock()

getblk.c:
- changed name of DC coef. predictors (cf. getpict.c)


94/05/08 sE

getblk.c getvlc.h:
- changed format of the DCT coefficient tables to a more readable (though
  less efficient) format by semi-automatic conversion, added comments

store.c:
- changed suffixes of seperate component files from .y/.u/.v to .Y/.U/.V
- added matrix_coefficients dependency of color space conversion
  for RGB output formats

gethdr.c:
- made matrix_coefficients global (used by store.c)
- changed frame_centre_horizontal_offset and frame_centre_vertical_offset
  from unsigned to signed bitstring (simsbf)
- fixed wrong sign extension of llx0, lly0


94/04/?? sE

first preliminary alpha release