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diff --git a/libjpegtwrp/asm/armv7/jdidct-armv7.S b/libjpegtwrp/asm/armv7/jdidct-armv7.S
new file mode 100644
index 000000000..d61e219f7
--- /dev/null
+++ b/libjpegtwrp/asm/armv7/jdidct-armv7.S
@@ -0,0 +1,762 @@
+/*=========================================================================
+* jdidct-armv7.s
+*
+*  Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+*
+*  Redistribution and use in source and binary forms, with or without
+*  modification, are permitted provided that the following conditions are
+*  met:
+*      * Redistributions of source code must retain the above copyright
+*        notice, this list of conditions and the following disclaimer.
+*      * Redistributions in binary form must reproduce the above
+*        copyright notice, this list of conditions and the following
+*        disclaimer in the documentation and/or other materials provided
+*        with the distribution.
+*      * Neither the name of Code Aurora Forum, Inc. nor the names of its
+*        contributors may be used to endorse or promote products derived
+*        from this software without specific prior written permission.
+*
+*  THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+*  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+*  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+*  ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
+*  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+*  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+*  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+*  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+*  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
+*  OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+*  IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*==========================================================================
+
+*==========================================================================
+*                         FUNCTION LIST
+*--------------------------------------------------------------------------
+* - idct_1x1_venum
+* - idct_2x2_venum
+* - idct_4x4_venum
+* - idct_8x8_venum
+*
+*==========================================================================
+*/
+
+@==========================================================================
+@ MACRO DEFINITION
+@==========================================================================
+    .macro Transpose8x8
+        @==================================================================
+        @ Transpose an 8 x 8 x 16 bit matrix in place
+        @ Input: q8 to q15
+        @ Output: q8 to q15
+        @ Registers used: q8 to q15
+        @ Assumptions: 8 x 8 x 16 bit data
+        @==================================================================
+
+        vswp d17, d24                  @q8, q12
+        vswp d23, d30                  @q11, q15
+        vswp d21, d28                  @q10, q14
+        vswp d19, d26                  @q9, q13
+
+        vtrn.32 q8,  q10
+        vtrn.32 q9,  q11
+        vtrn.32 q12, q14
+        vtrn.32 q13, q15
+
+        vtrn.16 q8,  q9
+        vtrn.16 q10, q11
+        vtrn.16 q12, q13
+        vtrn.16 q14, q15
+    .endm
+
+    .macro IDCT1D
+        @==================================================================
+        @ One dimensional 64 element inverse DCT
+        @ Input: q8 to q15 loaded with data
+        @        q0 loaded with constants
+        @ Output: q8 to q15
+        @ Registers used: q0, q4 to q15
+        @ Assumptions: 16 bit data, first elements in least significant
+        @ halfwords
+        @==================================================================
+
+        @1st stage
+        vqrdmulh.s16 q4,  q15, d0[2]   @q4 = a1*vx7
+        vqrdmulh.s16 q5,  q9,  d0[2]   @q5 = a1*vx1
+        vqrdmulh.s16 q6,  q13, d0[3]   @q6 = a2*vx5
+        vqrdmulh.s16 q7,  q11, d1[1]   @q7 = ma2*vx3
+        vqrdmulh.s16 q2,  q14, d0[1]   @q6 = a0*vx6
+        vqrdmulh.s16 q3,  q10, d0[1]   @q7 = a0*vx2
+        vqadd.s16   q9,  q4,  q9       @q9 = t1 = a1*vx7 + vx1
+        vqsub.s16   q5,  q5,  q15      @q5 = t8 = a1*vx1 - vx7
+        vqadd.s16   q15, q6,  q11      @q15 = t7 = a2*vx5 + vx3
+        vqadd.s16   q11, q7,  q13      @q11 = t3 = ma2*vx3 + vx5
+
+        @2nd stage
+        vqadd.s16   q13, q8,  q12      @q13 = t5 = vx0 + vx4
+        vqsub.s16   q8,  q8,  q12      @q8 = t0 = vx0 - vx4
+        vqadd.s16   q10, q2,  q10      @q10 = t2 = a0*vx6 + vx2
+        vqsub.s16   q12, q3,  q14      @q12 = t4 = a0*vx2 - vx6
+        vqadd.s16   q14, q5,  q11      @q14 = t6 = t8 + t3
+        vqsub.s16   q11, q5,  q11      @q11 = t3 = t8 - t3
+        vqsub.s16   q5,  q9,  q15      @q5 = t8 = t1 - t7
+        vqadd.s16   q9,  q9,  q15      @q9 = t1 = t1 + t7
+
+        @3rd stage
+        vqadd.s16   q15, q13, q10      @q15 = t7 = t5 + t2
+        vqsub.s16   q10, q13, q10      @q10 = t2 = t5 - t2
+        vqadd.s16   q13, q8,  q12      @q13 = t5 = t0 + t4
+        vqsub.s16   q7,  q8,  q12      @q7 = t0 = t0 - t4
+        vqsub.s16   q12, q5,  q11      @q12 = t4 = t8 - t3
+        vqadd.s16   q11, q5,  q11      @q11 = t3 = t8 + t3
+
+        @4th stage
+        vqadd.s16   q8,  q15, q9       @q8 = vy0 = t7 + t1
+        vqsub.s16   q15, q15, q9       @q15 = vy7 = t7 - t1
+        vqrdmulh.s16 q6,  q12, d0[0]   @q6 = c4*t4
+        vqrdmulh.s16 q4,  q11, d0[0]   @q4 = c4*t3
+        vqsub.s16   q12, q10, q14      @q12 = vy4 = t2 - t6
+        vqadd.s16   q11, q10, q14      @q11 = vy3 = t2 + t6
+        vqadd.s16   q10, q7,  q6       @q10 = vy2 = t0 + c4*t4
+        vqsub.s16   q14, q13, q4       @q14 = vy6 = t5 - c4*t3
+        vqadd.s16   q9,  q13, q4       @q9 = vy1 = t5 + c4*t3
+        vqsub.s16   q13, q7,  q6       @q13 = vy5 = t0 - c4*t4
+    .endm
+
+    .macro PART1
+        @==================================================================
+        @ Load input input data from memory and shift
+        @==================================================================
+        vld1.16   {d16, d17},[r0]!     @q8 =row0
+        vqshl.s16  q8,  q8,  #4        @Input data too big?!!
+                                       @Maximum MPEG input is 2047/-2048.
+        vld1.16   {d18, d19},[r0]!     @q9 =row1
+        vqshl.s16  q9,  q9,  #4        @Shift 1 instead of 4
+
+        vld1.16   {d20, d21},[r0]!     @q10=row2
+        vqshl.s16  q10, q10, #4
+
+        vld1.16   {d22, d23},[r0]!     @q11=row3
+        vqshl.s16  q11, q11, #4
+
+        vld1.16   {d24, d25},[r0]!     @q12=row4
+        vqshl.s16  q12, q12, #4
+
+        vld1.16   {d26, d27},[r0]!     @q13=row5
+        vqshl.s16  q13, q13, #4
+        vld1.16   {d28, d29},[r0]!     @q14=row6
+        vqshl.s16  q14, q14, #4
+        vld1.16   {d30, d31},[r0]!     @q15=row7
+        vqshl.s16  q15, q15, #4
+
+        @==================================================================
+        @ refresh the constants that was clobbered last time through IDCT1D
+        @==================================================================
+        vld1.16   {d4, d5},[r7]        @q2 =constants[2]
+        vld1.16   {d6, d7},[r8]        @q3 =constants[3]
+        vld1.16   {d8, d9},[r9]        @q4 =constants[4]
+    .endm
+
+    .macro PART2
+        @==================================================================
+        @ Prescale the input
+        @==================================================================
+        vqrdmulh.s16 q12, q12, q1      @q12=row4 * constants[1] = vx4
+        vqrdmulh.s16 q15, q15, q2      @q15=row7 * constants[2] = vx7
+        vqrdmulh.s16 q9,  q9,  q2      @q9 =row1 * constants[2] = vx1
+        vqrdmulh.s16 q13, q13, q4      @q13=row5 * constants[4] = vx5
+        vqrdmulh.s16 q11, q11, q4      @q11=row3 * constants[4] = vx3
+        vqrdmulh.s16 q14, q14, q3      @q14=row6 * constants[3] = vx6
+        vqrdmulh.s16 q10, q10, q3      @q10=row2 * constants[3] = vx2
+        vqrdmulh.s16 q8,  q8,  q1      @q8 =row0 * constants[1] = vx0
+
+        @==================================================================
+        @ At thsi point, the input 8x8 x 16 bit coefficients are
+        @ transposed, prescaled, and loaded in q8 to q15
+        @ q0 loaded with scalar constants
+        @ Perform 1D IDCT
+        @==================================================================
+        IDCT1D                         @perform 1d idct
+
+        @==================================================================
+        @ Transpose the intermediate results to get read for vertical
+        @ transformation
+        @==================================================================
+        vswp d17, d24                  @q8, q12
+        vswp d23, d30                  @q11, q15
+        vswp d21, d28                  @q10, q14
+        vswp d19, d26                  @q9, q13
+
+        @==================================================================
+        @ Load the bias
+        @==================================================================
+        vdup.32 q4, d1[1]              @a cycle is saved by loading
+                                       @the bias at this point
+
+        @==================================================================
+        @ Finish the transposition
+        @==================================================================
+        vtrn.32 q8,  q10
+        vtrn.32 q9,  q11
+        vtrn.32 q12, q14
+        vtrn.32 q13, q15
+        vtrn.16 q8,  q9
+        vtrn.16 q10, q11
+        vtrn.16 q12, q13
+        vtrn.16 q14, q15
+
+        @==================================================================
+        @ Add bias
+        @==================================================================
+        vqadd.s16 q8, q8, q4
+
+        @==================================================================
+        @ IDCT 2nd half
+        @==================================================================
+        IDCT1D                         @perform 1d dct
+
+        @==================================================================
+        @ Scale and clamp the output to correct range and save to memory
+        @ 1. scale to 8bits by right shift 6
+        @ 2. clamp output to [0, 255] by min/max
+        @ 3. use multiple store. Each store will save one row of output.
+        @    The st queue size is 4, so do no more than 4 str in sequence.
+        @==================================================================
+        ldr       r5, =constants+5*16  @constants[5],
+        vld1.16   d10, [r5]            @load clamping parameters
+        vdup.s16  q6,  d10[0]          @q6=[0000000000000000]
+        vdup.s16  q7,  d10[1]          @q7=[FFFFFFFFFFFFFFFF]
+
+        @Save the results
+        vshr.s16  q8,  q8,  #6         @q8 = vy0
+        vmax.s16  q8,  q8,  q6         @clamp >0
+        vmin.s16  q8,  q8,  q7         @clamp <255
+
+        vshr.s16  q9,  q9,  #6         @q9 = vy1
+        vmax.s16  q9,  q9,  q6         @clamp >0
+        vmin.s16  q9,  q9,  q7         @clamp <255
+
+        vshr.s16  q10, q10, #6         @q10 = vy2
+        vmax.s16  q10, q10, q6         @clamp >0
+        vmin.s16  q10, q10, q7         @clamp <255
+
+        vshr.s16  q11, q11, #6         @q11 = vy3
+        vmax.s16  q11, q11, q6         @clamp >0
+        vmin.s16  q11, q11, q7         @clamp <255
+
+        vst1.16  {d16, d17},[r1],r2    @q8 =row0
+        vst1.16  {d18, d19},[r1],r2    @q9 =row1
+        vst1.16  {d20, d21},[r1],r2    @q10=row2
+        vst1.16  {d22, d23},[r1],r2    @q11=row3
+
+        vshr.s16  q12, q12, #6         @q12 = vy4
+        vmax.s16  q12, q12, q6         @clamp >0
+        vmin.s16  q12, q12, q7         @clamp <255
+
+        vshr.s16  q13, q13, #6         @q13 = vy5
+        vmax.s16  q13, q13, q6         @clamp >0
+        vmin.s16  q13, q13, q7         @clamp <255
+
+        vshr.s16  q14, q14, #6         @q14 = vy6
+        vmax.s16  q14, q14, q6         @clamp >0
+        vmin.s16  q14, q14, q7         @clamp <255
+
+        vshr.s16  q15, q15, #6         @q15 = vy7
+        vmax.s16  q15, q15, q6         @clamp >0
+        vmin.s16  q15, q15, q7         @clamp <255
+
+        vst1.16  {d24, d25},[r1],r2    @q12=row4
+        vst1.16  {d26, d27},[r1],r2    @q13=row5
+        vst1.16  {d28, d29},[r1],r2    @q14=row6
+        vst1.16  {d30, d31},[r1]       @q15=row7
+    .endm
+
+    .macro BIG_BODY_TRANSPOSE_INPUT
+        @==================================================================
+        @ Main body of idct
+        @==================================================================
+        PART1
+        Transpose8x8
+        PART2
+    .endm
+
+    .macro IDCT_ENTRY
+        @==================================================================
+        @ Load the locations of the constants
+        @==================================================================
+        ldr  r5,  =constants+0*16      @constants[0]
+        ldr  r6,  =constants+1*16      @constants[1]
+        ldr  r7,  =constants+2*16      @constants[2]
+        ldr  r8,  =constants+3*16      @constants[3]
+        ldr  r9,  =constants+4*16      @constants[4]
+
+        @==================================================================
+        @ Load the coefficients
+        @ only some input coefficients are load due to register constrain
+        @==================================================================
+        vld1.16   {d0, d1},[r5]        @q0 =constants[0] (scalars)
+        vld1.16   {d2, d3},[r6]        @q1 =constants[1]
+    .endm
+@==========================================================================
+@ END of MACRO DEFINITION
+@==========================================================================
+
+
+    .section idct_func, "x"            @ ARE
+    .text                              @ idct_func, CODE, READONLY
+    .align 2
+    .code 32                           @ CODE32
+
+@==========================================================================
+@ Main Routine
+@==========================================================================
+
+    .global idct_1x1_venum
+    .global idct_2x2_venum
+    .global idct_4x4_venum
+    .global idct_8x8_venum
+
+@==========================================================================
+@ FUNCTION     : idct_1x1_venum
+@--------------------------------------------------------------------------
+@ DISCRIPTION  : ARM optimization of one 1x1 block iDCT
+@--------------------------------------------------------------------------
+@ C PROTOTYPE  : void idct_1x1_venum(int16 * input,
+@                                    int16 * output,
+@                                    int32 stride)
+@--------------------------------------------------------------------------
+@ REG INPUT    : R0 pointer to input (int16)
+@                R1 pointer to output (int16)
+@                R2 block stride
+@--------------------------------------------------------------------------
+@ STACK ARG    : None
+@--------------------------------------------------------------------------
+@ MEM INPUT    : None
+@--------------------------------------------------------------------------
+@ REG OUTPUT   : None
+@--------------------------------------------------------------------------
+@ MEM OUTPUT   : None
+@--------------------------------------------------------------------------
+@ REG AFFECTED : R0 - R2
+@--------------------------------------------------------------------------
+@ STACK USAGE  : none
+@--------------------------------------------------------------------------
+@ CYCLES       : 17 cycles
+@--------------------------------------------------------------------------
+@ NOTES        :
+@ This idct_1x1_venum code was developed with ARM instruction set.
+@
+@ ARM REGISTER ALLOCATION
+@ =========================================================================
+@ r0  : pointer to input data
+@ r1  : pointer to output area
+@ r2  : stride in the output buffer
+@==========================================================================
+.type idct_1x1_venum, %function
+idct_1x1_venum:
+
+    ldrsh   r3, [r0]                   @ Load signed half word (int16)
+    ldr     r2, =1028                  @ 1028 = 4 + 128 << 3
+                                       @ 4 for rounding, 128 for offset
+    add     r2, r3, r2
+    asrs    r2, r2, #3                 @ Divide by 8, and set status bit
+    movmi   r2, #0                     @ Clamp to be greater than 0
+    cmp     r2, #255
+    movgt   r2, #255                   @ Clamp to be less than 255
+    str     r2, [r1]                   @ Save output
+    bx      lr                         @ Return to caller
+
+                                       @ end of idct_1x1_venum
+
+
+@==========================================================================
+@ FUNCTION     : idct_2x2_venum
+@--------------------------------------------------------------------------
+@ DISCRIPTION  : VeNum optimization of one 2x2 block iDCT
+@--------------------------------------------------------------------------
+@ C PROTOTYPE  : void idct_2x2_venum(int16 * input,
+@                                    int16 * output,
+@                                    int32 stride)
+@--------------------------------------------------------------------------
+@ REG INPUT    : R0 pointer to input (int16)
+@                R1 pointer to output (int16)
+@                R2 block stride
+@--------------------------------------------------------------------------
+@ STACK ARG    : None
+@--------------------------------------------------------------------------
+@ MEM INPUT    : None
+@--------------------------------------------------------------------------
+@ REG OUTPUT   : None
+@--------------------------------------------------------------------------
+@ MEM OUTPUT   : None
+@--------------------------------------------------------------------------
+@ REG AFFECTED : R0 - R2
+@--------------------------------------------------------------------------
+@ STACK USAGE  : none
+@--------------------------------------------------------------------------
+@ CYCLES       : 27 cycles
+@--------------------------------------------------------------------------
+@ NOTES        : Output buffer must be an 8x8 16-bit buffer
+@
+@ ARM REGISTER ALLOCATION
+@ ==========================================
+@ r0  : pointer to input data
+@ r1  : pointer to output area
+@ r2  : stride in the output buffer
+@ -------------------------------------------
+@
+@ VENUM REGISTER ALLOCATION
+@ =================================================
+@ q0     : output x0 - x4
+@ q1     : not used
+@ q2     : not used
+@ q3     : not used
+@ q4     : not used
+@ q5     : not used
+@ q6     : not used
+@ q7     : not used
+@ q8     : input y0 - y4
+@ q9     : intermediate value
+@ q10    : intermediate value
+@ q11    : offset value
+@ q12    : clamp value
+@ q13    : not used
+@ q14    : not used
+@ q15    : not used
+@==========================================================================
+.type idct_2x2_venum, %function
+idct_2x2_venum:
+
+    vld4.32    {d16, d17, d18, d19}, [r0]
+                                       @  d16: y0 | y1 | y2 | y3  (LSB | MSB)
+
+    vtrn.32    d16, d17                @  d16: y0 | y1 | X | X
+                                       @  d17: y2 | y3 | X | X
+
+    vqadd.s16  d18, d16, d17           @ d18: y0+y2 | y1+y3 | X | X   q: saturated
+    vqsub.s16  d19, d16, d17           @ d19: y0-y2 | y1-y3 | X | X   q: saturated
+
+    vtrn.16    d18, d19                @ d18: y0+y2 | y0-y2 | X | X
+                                       @ d19: y1+y3 | y1-y3 | X | X
+
+    vqadd.s16  d20, d18, d19           @ d20: (y0+y2)+(y1+y3) | (y0-y2)+(y1-y3)
+                                       @       x0 | x2 | X | X
+    vqsub.s16  d21, d18, d19           @ d21: (y0+y2)-(y1+y3) | (y0-y2)-(y1-y3)
+                                       @       x1 | x3 | X | X
+
+    vtrn.16    d20, d21                @ d20:  x0 | x1 | X | X
+                                       @ d21:  x2 | x3 | X | X
+
+    vrshr.s16  q10, q10, #3               @ Divide by 8
+
+    vmov.i16   q11, #128               @ q11 = 128|128|128|128|128|128|128|128
+    vqadd.s16  q0, q10, q11            @ Add offset to make output in [0,255]
+
+    vmov.i16   q12, #0                   @ q12 = [0000000000000000]
+    vmov.i16   q13, #255               @ q13 = [FFFFFFFFFFFFFFFF] (hex)
+
+    vmax.s16   q0, q0, q12             @ Clamp > 0
+    vmin.s16   q0, q0, q13             @ Clamp < 255
+
+    vstr       d0, [r1]                @ Store  x0 | x1 | X | X
+                                       @ Potential out of boundary issue
+    add        r1, r1, r2              @ Add the offset to the output pointer
+    vstr       d1, [r1]                @ Store  x2 | x3 | X | X
+                                       @ Potential out of boundary issue
+    bx         lr                      @ Return to caller
+
+                                       @ end of idct_2x2_venum
+
+
+@==========================================================================
+@ FUNCTION     : idct_4x4_venum
+@--------------------------------------------------------------------------
+@ DISCRIPTION  : VeNum optimization of one 4x4 block iDCT
+@--------------------------------------------------------------------------
+@ C PROTOTYPE  : void idct_4x4_venum(int16 * input,
+@                                    int16 * output,
+@                                    int32 stride)
+@--------------------------------------------------------------------------
+@ REG INPUT    : R0 pointer to input (int16)
+@                R1 pointer to output (int16)
+@                R2 block stride
+@--------------------------------------------------------------------------
+@ STACK ARG    : None
+@--------------------------------------------------------------------------
+@ MEM INPUT    : None
+@--------------------------------------------------------------------------
+@ REG OUTPUT   : None
+@--------------------------------------------------------------------------
+@ MEM OUTPUT   : None
+@--------------------------------------------------------------------------
+@ REG AFFECTED : R0 - R3, R12
+@--------------------------------------------------------------------------
+@ STACK USAGE  : none
+@--------------------------------------------------------------------------
+@ CYCLES       : 56 cycles
+@--------------------------------------------------------------------------
+@ NOTES        :
+@
+@ ARM REGISTER ALLOCATION
+@ ==========================================
+@ r0  : pointer to input data
+@ r1  : pointer to output area
+@ r2  : stride in the output buffer
+@ r3  : pointer to the coefficient set
+@ r12 : pointer to the coefficient set
+@ -------------------------------------------
+@
+@ VENUM REGISTER ALLOCATION
+@ =================================================
+@ q0     : coefficients[0]
+@ q1     : coefficients[1]
+@ q2     : coefficients[2]
+@ q3     : coefficients[3]
+@ q4     : not used
+@ q5     : not used
+@ q6     : not used
+@ q7     : not used
+@ q8     : input y0 - y7
+@ q9     : input y8 - y15
+@ q10    : intermediate value
+@ q11    : intermediate value
+@ q12    : intermediate value
+@ q13    : intermediate value
+@ q14    : intermediate value
+@ q15    : intermediate value
+@==========================================================================
+.type idct_4x4_venum, %function
+idct_4x4_venum:
+
+        @ Load the locations of the first 2 sets of coefficients
+        ldr  r3,   =coefficient+0*16   @ coefficient[0]
+        ldr  r12,  =coefficient+1*16   @ coefficient[1]
+
+        @ Load the first 2 sets of coefficients
+        vld1.16  {d0, d1},[r3]         @ q0 = C4 | C2 | C4 | C6 | C4 | C2 | C4 | C6
+        vld1.16  {d2, d3},[r12]        @ q1 = C4 | C6 | C4 | C2 | C4 | C6 | C4 | C2
+
+        @ Load the locations of the second 2 sets of coefficients
+        ldr  r3,   =coefficient+2*16   @ coefficient[2]
+        ldr  r12,  =coefficient+3*16   @ coefficient[3]
+
+        @ Load the second 2 sets of coefficients
+        vld1.16  {d4, d5},[r3]         @ q2 = C4 | C4 | C4 | C4 | C2 | C2 | C2 | C2
+        vld1.16  {d6, d7},[r12]        @ q3 = C4 | C4 | C4 | C4 | C6 | C6 | C6 | C6
+
+        @ Load the input values
+        vld1.16  {d16}, [r0], r2       @ d16:   y0  | y1  | y2  | y3  (LSB | MSB)
+        vld1.16  {d17}, [r0], r2       @ d17:   y4  | y5  | y6  | y7  (LSB | MSB)
+        vld1.16  {d18}, [r0], r2       @ d18:   y8  | y9  | y10 | y11 (LSB | MSB)
+        vld1.16  {d19}, [r0], r2       @ d19:   y12 | y13 | y14 | y15 (LSB | MSB)
+
+        @ Apply iDCT Horizonally
+
+        @ q8: y0 |y1 |y2 |y3 |y4 |y5 |y6 |y7
+        @ q9: y8 |y9 |y10|y11|y12|y13|y14|y15
+
+        @======================================================================
+        @ vqrdmulh doubles the result and save the high 16 bits of the result,
+        @ this is equivalent to right shift by 15 bits.
+        @ since coefficients are in Q15 format, it contradicts with the right
+        @ shift 15 here, so the final result is in Q0 format
+        @
+        @ vqrdmulh will also round the result
+        @======================================================================
+
+        vqrdmulh.s16  q10, q8, q0      @ q10: C4*y0  | C2*y1  | C4*y2  | C6*y3  | C4*y4  | C2*y5  | C4*y6  | C6*y7
+        vqrdmulh.s16  q11, q8, q1      @ q11: C4*y0  | C6*y1  | C4*y2  | C2*y3  | C4*y4  | C6*y5  | C4*y6  | C2*y7
+
+        vqrdmulh.s16  q12, q9, q0      @ q12: C4*y8  | C2*y9  | C4*y10 | C6*y11 | C4*y12 | C2*y13 | C4*y14 | C6*y15
+        vqrdmulh.s16  q13, q9, q1      @ q13: C4*y8  | C6*y9  | C4*y10 | C2*y11 | C4*y12 | C6*y13 | C4*y14 | C2*y15
+
+        vtrn.32       q10, q12         @ q10: C4*y0  | C2*y1  | C4*y8  | C2*y9  | C4*y4  | C2*y5  | C4*y12 | C2*y13
+                                       @ q12: C4*y2  | C6*y3  | C4*y10 | C6*y11 | C4*y6  | C6*y7  | C4*y14 | C6*y15
+
+        vtrn.32       q11, q13         @ q11: C4*y0  | C6*y1  | C4*y8  | C6*y9  | C4*y4  | C6*y5  | C4*y12 | C6*y13
+                                       @ q13: C4*y2  | C2*y3  | C4*y10 | C2*y11 | C4*y6  | C2*y7  | C4*y14 | C2*y15
+
+        vqadd.s16     q14, q10, q12    @ q14: C4*y0 + C4*y2 | C2*y1 + C6*y3 | C4*y8 + C4*y10 | C2*y9 + C6*y11 | C4*y4 + C4*y6 | C2*y5 + C6*y7 | C4*y12 + C4*y14 | C2*y13 + C6*y15
+                                       @       S0 | S2 | S8 | S10 | S4 | S6 | S12 | S14
+
+        vqsub.s16     q15, q11, q13    @ q15: C4*y0 - C4*y2 | C6*y1 - C2*y3 | C4*y8 - C4*y10 | C6*y9 - C2*y11 | C4*y4 - C4*y6 | C6*y5 - C2*y7 | C4*y12 - C4*y14 | C6*y13 - C2*y15
+                                       @       S1 | S3 | S9 | S11 | S5 | S7 | S13 | S15
+
+        vtrn.16       q14, q15         @ q14: S0 | S1 | S8  | S9  | S4 | S5 | S12 | S13
+                                       @ q15: S2 | S3 | S10 | S11 | S6 | S7 | S14 | S15
+
+        vqadd.s16     q8, q14, q15     @ q8:  Z0 | Z1 | Z8  | Z9  | Z4 | Z5 | Z12 | Z13
+        vqsub.s16     q9, q14, q15     @ q9:  Z3 | Z2 | Z11 | Z10 | Z7 | Z6 | Z15 | Z14
+        vrev32.16     q9, q9           @ q9:  Z2 | Z3 | Z10 | Z11 | Z6 | Z7 | Z14 | Z15
+
+
+        @ Apply iDCT Vertically
+
+        vtrn.32       q8, q9           @ q8:  Z0 | Z1 | Z2  | Z3  | Z4  | Z5  | Z6  | Z7
+                                       @ q9:  Z8 | Z9 | Z10 | Z11 | Z12 | Z13 | Z14 | Z15
+
+
+        vqrdmulh.s16  q10, q8, q2      @ q10: C4*Z0 | C4*Z1 | C4*Z2 | C4*Z3 | C2*Z4 | C2*Z5 | C2*Z6 | C2*Z7
+        vqrdmulh.s16  q11, q8, q3      @ q11: C4*Z0 | C4*Z1 | C4*Z2 | C4*Z3 | C6*Z4 | C6*Z5 | C6*Z6 | C6*Z7
+
+        vqrdmulh.s16  q12, q9, q2      @ q12: C4*Z8 | C4*Z9 | C4*Z10 | C4*Z11 | C2*Z12 | C2*Z13 | C2*Z14 | C2*Z15
+        vqrdmulh.s16  q13, q9, q3      @ q13: C4*Z8 | C4*Z9 | C4*Z10 | C4*Z11 | C6*Z12 | C6*Z13 | C6*Z14 | C6*Z15
+
+        vqadd.s16     q14, q10, q13    @ q14: C4*Z0+C4*Z8 | C4*Z1+C4*Z9 | C4*Z2+C4*Z10 | C4*Z3+C4*Z11 | C2*Z4+C6*Z12 | C2*Z5+C6*Z13 | C2*Z6+C6*Z14 | C2*Z7+C6*Z15
+                                       @      s0 | s4 | s8 | s12 | s2 | s6 | s10 | s14
+
+        vqsub.s16     q15, q11, q12    @ q15: C4*Z0-C4*Z8 | C4*Z1-C4*Z9 | C4*Z2-C4*Z10 | C4*Z3-C4*Z11 | C6*Z4-C2*Z12 | C6*Z5-C2*Z13 | C6*Z6-C2*Z14 | C6*Z7-C2*Z15
+                                       @      s1 | s5 | s9 | s13 | s3 | s7 | s11 | s15
+
+        vswp          d29, d30         @ q14: s0 | s4 | s8  | s12 | s1 | s5 | s9  | s13
+                                       @ q15: s2 | s6 | s10 | s14 | s3 | s7 | s11 | s15
+
+        vqadd.s16     q8, q14, q15     @ q8:  x0 | x4 | x8  | x12 | x1 | x5 | x9 | x13
+        vqsub.s16     q9, q14, q15     @ q9:  x3 | x7 | x11 | x15 | x2 | x6 | x10 | x14
+
+        vmov.i16      q10, #0           @ q10=[0000000000000000]
+        vmov.i16      q11, #255        @ q11=[FFFFFFFFFFFFFFFF] (hex)
+
+        vmov.i16      q0, #128         @ q0 = 128|128|128|128|128|128|128|128
+
+        vqadd.s16     q8, q8, q0       @ Add the offset
+        vqadd.s16     q9, q9, q0       @ Add the offset
+
+        vmax.s16      q8, q8, q10      @ clamp > 0
+        vmin.s16      q8, q8, q11      @ clamp < 255
+
+        vmax.s16      q9, q9, q10      @ clamp > 0
+        vmin.s16      q9, q9, q11      @ clamp < 255
+
+        vst1.16       {d16}, [r1], r2  @  d16:   x0 | x1  | x2  | x3  (LSB | MSB)
+        vst1.16       {d17}, [r1], r2  @  d17:   x4 | x5  | x6  | x7  (LSB | MSB)
+        vst1.16       {d19}, [r1], r2  @  d18:   x8 | x9  | x10 | x11 (LSB | MSB)
+        vst1.16       {d18}, [r1], r2  @  d19:   x12| x13 | x14 | x15 (LSB | MSB)
+
+        bx         lr                  @ Return to caller
+
+                                       @ end of idct_4x4_venum
+
+@==========================================================================
+@ FUNCTION     : idct_8x8_venum
+@--------------------------------------------------------------------------
+@ DISCRIPTION  : VeNum optimization of one 8x8 block iDCT
+@--------------------------------------------------------------------------
+@ C PROTOTYPE  : void idct_8x8_venum(int16 * input,
+@                                    int16 * output,
+@                                    int32 stride)
+@--------------------------------------------------------------------------
+@ REG INPUT    : R0 pointer to input (int16)
+@                R1 pointer to output (int16)
+@                R2 block stride
+@--------------------------------------------------------------------------
+@ STACK ARG    : None
+@--------------------------------------------------------------------------
+@ MEM INPUT    : None
+@--------------------------------------------------------------------------
+@ REG OUTPUT   : None
+@--------------------------------------------------------------------------
+@ MEM OUTPUT   : None
+@--------------------------------------------------------------------------
+@ REG AFFECTED : R0 - R9
+@--------------------------------------------------------------------------
+@ STACK USAGE  : none
+@--------------------------------------------------------------------------
+@ CYCLES       : 177 cycles
+@--------------------------------------------------------------------------
+@ NOTES        :
+@
+@ It was tested to be IEEE 1180 compliant. Since IEEE 1180 compliance is more stringent
+@ than MPEG-4 compliance, this version is also MPEG-4 compliant.
+@
+@ CODE STRUCTURE:
+@ (i)   Macros for transposing an 8x8 matrix and for configuring the VFP unit are defined.
+@ (ii)  Macro for IDCT in one dimension is defined as four stages
+@ (iii) The two dimensional code begins
+@ (iv)  constants are defined in the area DataArea
+@
+@ PROGRAM FLOW:
+@
+@ The VFP is configured
+@ The parameters to IDCT are loaded
+@ the coefficients are loaded
+@ loop:
+@    decrement loop counter
+@    The first input Matrix is loaded and pre-scaled
+@    The input is prescaled using the constants
+@    IDCT is performed in one dimension on the 8 columns
+@    The matrix is transposed
+@    A bias is loaded an added to the matrix
+@    IDCT is performed in one dimension on the 8 rows
+@    The matrix is post-scaled
+@    The matrix is saved
+@    test loop counter and loop if greater than zero
+@ stop
+@
+@
+@ ARM REGISTER ALLOCATION
+@ ==========================================
+@ r0 : pointer to input data
+@ r1 : pointer to output are
+@ r2 : stride in the output buffer
+@ r3 :
+@ r4 :
+@ r5 : pointer to constants[0] [5]
+@ r6 : pointer to constants[1]
+@ r7 : pointer to constants[2]
+@ r8 : pointer to constants[3]
+@ r9 : pointer to constants[4]
+@ -------------------------------------------
+@
+@ VENUM REGISTER ALLOCATION
+@ =================================================
+@ q0     : constants[0]
+@ q1     : constants[1]
+@ q2     : constants[2], IDCT1D in-place scratch
+@ q3     : constants[3], IDCT1D in-place scratch
+@ q4     : constants[4], IDCT1D in-place scratch, and bias compensation
+@ q5     :               IDCT1D in-place scratch
+@ q6     :               IDCT1D in-place scratch
+@ q7     :               IDCT1D in-place scratch
+@ q8     : Matrix[0]     IDCT1D in-place scratch
+@ q9     : Matrix[1]     IDCT1D in-place scratch
+@ q10    : Matrix[2]     IDCT1D in-place scratch
+@ q11    : Matrix[3]     IDCT1D in-place scratch
+@ q12    : Matrix[4]     IDCT1D in-place scratch
+@ q13    : Matrix[5]     IDCT1D in-place scratch
+@ q14    : Matrix[6]     IDCT1D in-place scratch
+@ q15    : Matrix[7]     IDCT1D in-place scratch
+@==========================================================================
+.type idct_8x8_venum, %function
+idct_8x8_venum:
+
+        push {r5-r9}
+        vpush {d8-d15}
+        IDCT_ENTRY
+        BIG_BODY_TRANSPOSE_INPUT
+        vpop {d8-d15}
+        pop  {r5-r9}
+        bx   lr
+                                       @ end of idct_8x8_venum
+
+@==========================================================================
+@ Constants Definition AREA: define idct kernel, bias
+@==========================================================================
+    .section ro_data_area              @ AREA  RODataArea
+    .data                              @ DATA, READONLY
+    .align 5                           @ ALIGN=5
+
+constants:
+        .hword  23170, 13573, 6518,  21895, -23170, -21895, 8223,  8224
+        .hword  16384, 22725, 21407, 19266, 16384,  19266,  21407, 22725
+        .hword  22725, 31521, 29692, 26722, 22725,  26722,  29692, 31521
+        .hword  21407, 29692, 27969, 25172, 21407,  25172,  27969, 29692
+        .hword  19266, 26722, 25172, 22654, 19266,  22654,  25172, 26722
+        .hword      0,   255,     0,     0
+
+coefficient:                           @ These are the coefficent used by 4x4 iDCT in Q15 format
+        .hword 11585, 15137,  11585,  6270, 11585, 15137,  11585,  6270  @ C4, C2, C4, C6, C4, C2, C4, C6 /2
+        .hword 11585,  6270,  11585, 15137, 11585,  6270,  11585, 15137  @ C4, C6, C4, C2, C4, C6, C4, C2 /2
+        .hword 11585, 11585,  11585, 11585, 15137, 15137,  15137, 15137  @ C4, C4, C4, C4, C2, C2, C2, C2 /2
+        .hword 11585, 11585,  11585, 11585,  6270,  6270,   6270,  6270  @ C4, C4, C4, C4, C6, C6, C6, C6 /2
+
+.end