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mikel262 |
-------------------------------------------------------------------------------
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-- File Name : Huffman.vhd
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--
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-- Project : JPEG_ENC
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--
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-- Module : Huffman
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--
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-- Content : Huffman Encoder
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--
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-- Description : Huffman encoder core
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--
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-- Spec. :
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--
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-- Author : Michal Krepa
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--
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-------------------------------------------------------------------------------
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-- History :
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-- 20090228: (MK): Initial Creation.
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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----------------------------------- LIBRARY/PACKAGE ---------------------------
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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-- generic packages/libraries:
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-------------------------------------------------------------------------------
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library ieee;
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use ieee.std_logic_1164.all;
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use ieee.numeric_std.all;
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-------------------------------------------------------------------------------
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-- user packages/libraries:
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-------------------------------------------------------------------------------
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mikel262 |
library work;
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use work.JPEG_PKG.all;
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mikel262 |
-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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----------------------------------- ENTITY ------------------------------------
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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entity Huffman is
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port
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(
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CLK : in std_logic;
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RST : in std_logic;
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-- CTRL
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start_pb : in std_logic;
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ready_pb : out std_logic;
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mikel262 |
huf_sm_settings : in T_SM_SETTINGS;
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mikel262 |
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-- HOST IF
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sof : in std_logic;
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img_size_x : in std_logic_vector(15 downto 0);
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img_size_y : in std_logic_vector(15 downto 0);
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cmp_max : in std_logic_vector(1 downto 0);
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-- RLE
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rle_buf_sel : out std_logic;
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rd_en : out std_logic;
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runlength : in std_logic_vector(3 downto 0);
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VLI_size : in std_logic_vector(3 downto 0);
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VLI : in std_logic_vector(11 downto 0);
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d_val : in std_logic;
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rle_fifo_empty : in std_logic;
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-- Byte Stuffer
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bs_buf_sel : in std_logic;
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bs_fifo_empty : out std_logic;
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bs_rd_req : in std_logic;
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bs_packed_byte : out std_logic_vector(7 downto 0)
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);
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end entity Huffman;
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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----------------------------------- ARCHITECTURE ------------------------------
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-------------------------------------------------------------------------------
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-------------------------------------------------------------------------------
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architecture RTL of Huffman is
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type T_STATE is (IDLE, RUN_VLC, RUN_VLI, PAD);
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constant C_M : integer := 23;
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constant BLK_SIZE : integer := 64;
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signal state : T_STATE;
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signal rle_buf_sel_s : std_logic;
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signal first_rle_word : std_logic;
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signal word_reg : unsigned(C_M-1 downto 0);
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signal bit_ptr : unsigned(4 downto 0);
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signal num_fifo_wrs : unsigned(1 downto 0);
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signal VLI_ext : unsigned(15 downto 0);
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signal VLI_ext_size : unsigned(4 downto 0);
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signal ready_HFW : std_logic;
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signal fifo_wbyte : std_logic_vector(7 downto 0);
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signal fifo_wrt_cnt : unsigned(1 downto 0);
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signal fifo_wren : std_logic;
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signal last_block : std_logic;
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signal image_area_size : unsigned(33 downto 0);
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signal block_cnt : unsigned(27 downto 0);
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signal VLC_size : unsigned(4 downto 0);
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signal VLC : unsigned(15 downto 0);
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signal VLC_DC_size : std_logic_vector(3 downto 0);
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signal VLC_DC : unsigned(8 downto 0);
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signal VLC_AC_size : unsigned(4 downto 0);
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signal VLC_AC : unsigned(15 downto 0);
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signal vlc_vld : std_logic;
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signal d_val_d1 : std_logic;
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signal d_val_d2 : std_logic;
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signal d_val_d3 : std_logic;
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signal d_val_d4 : std_logic;
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signal VLI_size_d : std_logic_vector(3 downto 0);
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signal VLI_d : std_logic_vector(11 downto 0);
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signal VLI_size_d1 : std_logic_vector(3 downto 0);
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signal VLI_d1 : std_logic_vector(11 downto 0);
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signal HFW_running : std_logic;
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signal runlength_r : std_logic_vector(3 downto 0);
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signal VLI_size_r : std_logic_vector(3 downto 0);
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signal VLI_r : std_logic_vector(11 downto 0);
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signal rd_en_s : std_logic;
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signal pad_byte : std_logic_vector(7 downto 0);
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signal pad_reg : std_logic;
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mikel262 |
signal VLC_CR_DC_size : std_logic_vector(3 downto 0);
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signal VLC_CR_DC : unsigned(10 downto 0);
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signal VLC_CR_AC_size : unsigned(4 downto 0);
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signal VLC_CR_AC : unsigned(15 downto 0);
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mikel262 |
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-------------------------------------------------------------------------------
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-- Architecture: begin
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-------------------------------------------------------------------------------
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begin
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rle_buf_sel <= rle_buf_sel_s;
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rd_en <= rd_en_s;
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vlc_vld <= rd_en_s;
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-------------------------------------------------------------------
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-- latch FIFO Q
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-------------------------------------------------------------------
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p_latch_fifo : process(CLK, RST)
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begin
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if RST = '1' then
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VLI_size_r <= (others => '0');
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VLI_r <= (others => '0');
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elsif CLK'event and CLK = '1' then
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if d_val = '1' then
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VLI_size_r <= VLI_size;
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VLI_r <= VLI;
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end if;
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end if;
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end process;
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-------------------------------------------------------------------
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mikel262 |
-- DC_ROM Luminance
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mikel262 |
-------------------------------------------------------------------
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U_DC_ROM : entity work.DC_ROM
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port map
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(
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CLK => CLK,
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RST => RST,
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VLI_size => VLI_size,
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VLC_DC_size => VLC_DC_size,
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VLC_DC => VLC_DC
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);
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-------------------------------------------------------------------
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mikel262 |
-- AC_ROM Luminance
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mikel262 |
-------------------------------------------------------------------
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U_AC_ROM : entity work.AC_ROM
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port map
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(
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CLK => CLK,
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RST => RST,
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runlength => runlength,
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VLI_size => VLI_size,
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VLC_AC_size => VLC_AC_size,
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VLC_AC => VLC_AC
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);
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mikel262 |
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-------------------------------------------------------------------
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-- DC_ROM Chrominance
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-------------------------------------------------------------------
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U_DC_CR_ROM : entity work.DC_CR_ROM
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port map
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(
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CLK => CLK,
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RST => RST,
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VLI_size => VLI_size,
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VLC_DC_size => VLC_CR_DC_size,
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VLC_DC => VLC_CR_DC
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);
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-------------------------------------------------------------------
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-- AC_ROM Chrominance
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-------------------------------------------------------------------
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U_AC_CR_ROM : entity work.AC_CR_ROM
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port map
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(
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CLK => CLK,
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RST => RST,
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runlength => runlength,
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VLI_size => VLI_size,
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VLC_AC_size => VLC_CR_AC_size,
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VLC_AC => VLC_CR_AC
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);
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mikel262 |
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-------------------------------------------------------------------
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-- Double Fifo
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-------------------------------------------------------------------
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U_DoubleFifo : entity work.DoubleFifo
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port map
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(
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CLK => CLK,
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RST => RST,
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-- HUFFMAN
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data_in => fifo_wbyte,
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wren => fifo_wren,
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-- BYTE STUFFER
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buf_sel => bs_buf_sel,
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rd_req => bs_rd_req,
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fifo_empty => bs_fifo_empty,
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data_out => bs_packed_byte
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);
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-------------------------------------------------------------------
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-- RLE buf_sel
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-------------------------------------------------------------------
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p_rle_buf_sel : process(CLK, RST)
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begin
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if RST = '1' then
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rle_buf_sel_s <= '0';
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elsif CLK'event and CLK = '1' then
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if start_pb = '1' then
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rle_buf_sel_s <= not rle_buf_sel_s;
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end if;
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end if;
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end process;
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-------------------------------------------------------------------
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mikel262 |
-- mux for DC/AC ROM Luminance/Chrominance
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mikel262 |
-------------------------------------------------------------------
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p_mux : process(CLK, RST)
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begin
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if RST = '1' then
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VLC_size <= (others => '0');
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VLC <= (others => '0');
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elsif CLK'event and CLK = '1' then
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mikel262 |
-- DC
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mikel262 |
if first_rle_word = '1' then
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mikel262 |
-- luminance
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if huf_sm_settings.cmp_idx = 0 then
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VLC_size <= unsigned('0' & VLC_DC_size);
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VLC <= resize(VLC_DC, VLC'length);
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-- chrominance
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else
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VLC_size <= unsigned('0' & VLC_CR_DC_size);
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VLC <= resize(VLC_CR_DC, VLC'length);
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end if;
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-- AC
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mikel262 |
else
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mikel262 |
-- luminance
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if huf_sm_settings.cmp_idx = 0 then
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VLC_size <= VLC_AC_size;
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VLC <= VLC_AC;
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-- chrominance
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else
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VLC_size <= VLC_CR_AC_size;
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VLC <= VLC_CR_AC;
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end if;
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mikel262 |
end if;
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end if;
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end process;
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-------------------------------------------------------------------
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-- Block Counter / Last Block detector
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-------------------------------------------------------------------
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p_blk_cnt : process(CLK, RST)
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begin
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if RST = '1' then
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image_area_size <= (others => '0');
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last_block <= '0';
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elsif CLK'event and CLK = '1' then
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image_area_size <= unsigned(cmp_max)*
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unsigned(img_size_x)*unsigned(img_size_y);
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if sof = '1' then
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block_cnt <= (others => '0');
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elsif start_pb = '1' then
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block_cnt <= block_cnt + 1;
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end if;
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299 |
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if block_cnt = image_area_size(33 downto 6) then
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last_block <= '1';
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else
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last_block <= '0';
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end if;
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end if;
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end process;
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308 |
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309 |
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VLI_ext <= unsigned("0000" & VLI_d1);
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VLI_ext_size <= unsigned('0' & VLI_size_d1);
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311 |
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312 |
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-------------------------------------------------------------------
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313 |
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-- delay line
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314 |
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-------------------------------------------------------------------
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315 |
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p_vli_dly : process(CLK, RST)
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316 |
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begin
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317 |
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if RST = '1' then
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VLI_d <= (others => '0');
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VLI_size_d <= (others => '0');
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320 |
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VLI_d1 <= (others => '0');
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VLI_size_d1 <= (others => '0');
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d_val_d1 <= '0';
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d_val_d2 <= '0';
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d_val_d3 <= '0';
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325 |
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d_val_d4 <= '0';
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326 |
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elsif CLK'event and CLK = '1' then
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VLI_d1 <= VLI_r;
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328 |
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VLI_size_d1 <= VLI_size_r;
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330 |
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VLI_d <= VLI_d1;
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VLI_size_d <= VLI_size_d1;
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332 |
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d_val_d1 <= d_val;
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d_val_d2 <= d_val_d1;
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d_val_d3 <= d_val_d2;
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d_val_d4 <= d_val_d3;
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end if;
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end process;
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339 |
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340 |
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-------------------------------------------------------------------
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341 |
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-- HandleFifoWrites
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342 |
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-------------------------------------------------------------------
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343 |
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p_HandleFifoWrites : process(CLK, RST)
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344 |
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begin
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345 |
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if RST = '1' then
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ready_HFW <= '0';
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347 |
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fifo_wrt_cnt <= (others => '0');
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348 |
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fifo_wren <= '0';
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349 |
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fifo_wbyte <= (others => '0');
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350 |
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rd_en_s <= '0';
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351 |
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elsif CLK'event and CLK = '1' then
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fifo_wren <= '0';
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353 |
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ready_HFW <= '0';
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354 |
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rd_en_s <= '0';
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355 |
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356 |
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if start_pb = '1' then
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357 |
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rd_en_s <= '1';
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358 |
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end if;
|
359 |
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|
360 |
|
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if HFW_running = '1' and ready_HFW = '0' then
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361 |
|
|
-- there is no at least one integer byte to write this time
|
362 |
|
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if num_fifo_wrs = 0 then
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363 |
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ready_HFW <= '1';
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364 |
|
|
if state = RUN_VLI then
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365 |
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rd_en_s <= '1';
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366 |
|
|
end if;
|
367 |
|
|
-- single byte write to FIFO
|
368 |
|
|
else
|
369 |
|
|
fifo_wrt_cnt <= fifo_wrt_cnt + 1;
|
370 |
|
|
fifo_wren <= '1';
|
371 |
|
|
-- last byte write
|
372 |
|
|
if fifo_wrt_cnt + 1 = num_fifo_wrs then
|
373 |
|
|
ready_HFW <= '1';
|
374 |
|
|
if state = RUN_VLI then
|
375 |
|
|
rd_en_s <= '1';
|
376 |
|
|
end if;
|
377 |
|
|
fifo_wrt_cnt <= (others => '0');
|
378 |
|
|
end if;
|
379 |
|
|
end if;
|
380 |
|
|
end if;
|
381 |
|
|
|
382 |
|
|
case fifo_wrt_cnt is
|
383 |
|
|
when "00" =>
|
384 |
|
|
fifo_wbyte <= std_logic_vector(word_reg(C_M-1 downto C_M-8));
|
385 |
|
|
when "01" =>
|
386 |
|
|
fifo_wbyte <= std_logic_vector(word_reg(C_M-8-1 downto C_M-16));
|
387 |
|
|
when others =>
|
388 |
|
|
fifo_wbyte <= (others => '0');
|
389 |
|
|
end case;
|
390 |
|
|
if pad_reg = '1' then
|
391 |
|
|
fifo_wbyte <= pad_byte;
|
392 |
|
|
end if;
|
393 |
|
|
|
394 |
|
|
|
395 |
|
|
end if;
|
396 |
|
|
end process;
|
397 |
|
|
|
398 |
|
|
-- divide by 8
|
399 |
|
|
num_fifo_wrs <= bit_ptr(4 downto 3);
|
400 |
|
|
|
401 |
|
|
-------------------------------------------------------------------
|
402 |
|
|
-- Variable Length Processor FSM
|
403 |
|
|
-------------------------------------------------------------------
|
404 |
|
|
p_vlp : process(CLK, RST)
|
405 |
|
|
begin
|
406 |
|
|
if RST = '1' then
|
407 |
|
|
ready_pb <= '0';
|
408 |
|
|
first_rle_word <= '0';
|
409 |
|
|
state <= IDLE;
|
410 |
|
|
word_reg <= (others => '0');
|
411 |
|
|
bit_ptr <= (others => '0');
|
412 |
|
|
HFW_running <= '0';
|
413 |
|
|
pad_reg <= '0';
|
414 |
|
|
pad_byte <= (others => '0');
|
415 |
|
|
elsif CLK'event and CLK = '1' then
|
416 |
|
|
ready_pb <= '0';
|
417 |
|
|
|
418 |
|
|
case state is
|
419 |
|
|
|
420 |
|
|
when IDLE =>
|
421 |
|
|
if start_pb = '1' then
|
422 |
|
|
first_rle_word <= '1';
|
423 |
|
|
state <= RUN_VLC;
|
424 |
|
|
end if;
|
425 |
|
|
|
426 |
|
|
when RUN_VLC =>
|
427 |
|
|
-- data valid DC or data valid AC
|
428 |
|
|
if (d_val_d2 = '1' and first_rle_word = '1') or
|
429 |
|
|
(d_val = '1' and first_rle_word = '0') then
|
430 |
|
|
for i in 0 to C_M-1 loop
|
431 |
|
|
if i < to_integer(VLC_size) then
|
432 |
|
|
word_reg(C_M-1-to_integer(bit_ptr)-i) <= VLC(to_integer(VLC_size)-1-i);
|
433 |
|
|
end if;
|
434 |
|
|
end loop;
|
435 |
|
|
bit_ptr <= bit_ptr + resize(VLC_size,bit_ptr'length);
|
436 |
|
|
|
437 |
|
|
-- HandleFifoWrites
|
438 |
|
|
HFW_running <= '1';
|
439 |
|
|
-- HandleFifoWrites completed
|
440 |
|
|
elsif HFW_running = '1' and
|
441 |
|
|
(num_fifo_wrs = 0 or fifo_wrt_cnt + 1 = num_fifo_wrs) then
|
442 |
|
|
-- shift word reg left to skip bytes already written to FIFO
|
443 |
|
|
word_reg <= shift_left(word_reg, to_integer(num_fifo_wrs & "000"));
|
444 |
|
|
-- adjust bit pointer after some bytes were written to FIFO
|
445 |
|
|
-- modulo 8 operation
|
446 |
|
|
bit_ptr <= bit_ptr - (num_fifo_wrs & "000");
|
447 |
|
|
HFW_running <= '0';
|
448 |
|
|
first_rle_word <= '0';
|
449 |
|
|
state <= RUN_VLI;
|
450 |
|
|
end if;
|
451 |
|
|
|
452 |
|
|
when RUN_VLI =>
|
453 |
|
|
if HFW_running = '0' then
|
454 |
|
|
|
455 |
|
|
for i in 0 to C_M-1 loop
|
456 |
|
|
if i < to_integer(VLI_ext_size) then
|
457 |
|
|
word_reg(C_M-1-to_integer(bit_ptr)-i)
|
458 |
|
|
<= VLI_ext(to_integer(VLI_ext_size)-1-i);
|
459 |
|
|
end if;
|
460 |
|
|
end loop;
|
461 |
|
|
|
462 |
|
|
bit_ptr <= bit_ptr + resize(VLI_ext_size,bit_ptr'length);
|
463 |
|
|
|
464 |
|
|
-- HandleFifoWrites
|
465 |
|
|
HFW_running <= '1';
|
466 |
|
|
-- HandleFifoWrites completed
|
467 |
|
|
elsif HFW_running = '1' and
|
468 |
|
|
(num_fifo_wrs = 0 or fifo_wrt_cnt + 1 = num_fifo_wrs) then
|
469 |
|
|
-- shift word reg left to skip bytes already written to FIFO
|
470 |
|
|
word_reg <= shift_left(word_reg, to_integer(num_fifo_wrs & "000"));
|
471 |
|
|
-- adjust bit pointer after some bytes were written to FIFO
|
472 |
|
|
-- modulo 8 operation
|
473 |
|
|
bit_ptr <= bit_ptr - (num_fifo_wrs & "000");
|
474 |
|
|
HFW_running <= '0';
|
475 |
|
|
|
476 |
|
|
-- end of block
|
477 |
|
|
if rle_fifo_empty = '1' then
|
478 |
|
|
-- end of segment
|
479 |
|
|
if bit_ptr - (num_fifo_wrs & "000") /= 0 and last_block = '1' then
|
480 |
|
|
state <= PAD;
|
481 |
|
|
else
|
482 |
|
|
ready_pb <= '1';
|
483 |
|
|
state <= IDLE;
|
484 |
|
|
end if;
|
485 |
|
|
else
|
486 |
|
|
state <= RUN_VLC;
|
487 |
|
|
end if;
|
488 |
|
|
end if;
|
489 |
|
|
|
490 |
|
|
-- end of segment which requires bit padding
|
491 |
|
|
when PAD =>
|
492 |
|
|
if HFW_running = '0' then
|
493 |
|
|
-- 1's bit padding to integer number of bytes
|
494 |
|
|
for i in 0 to 7 loop
|
495 |
|
|
if i < bit_ptr then
|
496 |
|
|
pad_byte(7-i) <= word_reg(C_M-1-i);
|
497 |
|
|
else
|
498 |
|
|
pad_byte(7-i) <= '1';
|
499 |
|
|
end if;
|
500 |
|
|
end loop;
|
501 |
|
|
pad_reg <= '1';
|
502 |
|
|
|
503 |
|
|
bit_ptr <= to_unsigned(8, bit_ptr'length);
|
504 |
|
|
|
505 |
|
|
-- HandleFifoWrites
|
506 |
|
|
HFW_running <= '1';
|
507 |
|
|
elsif HFW_running = '1' and
|
508 |
|
|
(num_fifo_wrs = 0 or fifo_wrt_cnt + 1 = num_fifo_wrs) then
|
509 |
|
|
bit_ptr <= (others => '0');
|
510 |
|
|
HFW_running <= '0';
|
511 |
|
|
pad_reg <= '0';
|
512 |
|
|
|
513 |
|
|
ready_pb <= '1';
|
514 |
|
|
state <= IDLE;
|
515 |
|
|
end if;
|
516 |
|
|
|
517 |
|
|
when others =>
|
518 |
|
|
|
519 |
|
|
end case;
|
520 |
|
|
|
521 |
|
|
if sof = '1' then
|
522 |
|
|
bit_ptr <= (others => '0');
|
523 |
|
|
end if;
|
524 |
|
|
|
525 |
|
|
end if;
|
526 |
|
|
end process;
|
527 |
|
|
|
528 |
|
|
|
529 |
|
|
end architecture RTL;
|
530 |
|
|
-------------------------------------------------------------------------------
|
531 |
|
|
-- Architecture: end
|
532 |
|
|
-------------------------------------------------------------------------------
|