/*

  * IBM Ultimotion Video Decoder

  * Copyright (C) 2004 Konstantin Shishkov
  *

  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either

  * version 2.1 of the License, or (at your option) any later version.

  *

  * FFmpeg is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  */
 
 /**

  * @file

  * IBM Ultimotion Video Decoder.
  */

 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "avcodec.h"

 #include "bytestream.h"

 #include "internal.h"

 
 #include "ulti_cb.h"
 
 typedef struct UltimotionDecodeContext {
     AVCodecContext *avctx;
     int width, height, blocks;

     AVFrame *frame;

     const uint8_t *ulti_codebook;

     GetByteContext gb;

 } UltimotionDecodeContext;
 

 static av_cold int ulti_decode_init(AVCodecContext *avctx)

 {
     UltimotionDecodeContext *s = avctx->priv_data;
 
     s->avctx = avctx;
     s->width = avctx->width;
     s->height = avctx->height;
     s->blocks = (s->width / 8) * (s->height / 8);

     avctx->pix_fmt = AV_PIX_FMT_YUV410P;

     s->ulti_codebook = ulti_codebook;

 
     s->frame = av_frame_alloc();
     if (!s->frame)
         return AVERROR(ENOMEM);

 
     return 0;
 }
 

 static av_cold int ulti_decode_end(AVCodecContext *avctx){
     UltimotionDecodeContext *s = avctx->priv_data;
 

     av_frame_free(&s->frame);

 
     return 0;
 }
 

 static const int block_coords[8] = // 4x4 block coords in 8x8 superblock

     { 0, 0, 0, 4, 4, 4, 4, 0};
 

 static const int angle_by_index[4] = { 0, 2, 6, 12};

 
 /* Lookup tables for luma and chroma - used by ulti_convert_yuv() */

 static const uint8_t ulti_lumas[64] =

     { 0x10, 0x13, 0x17, 0x1A, 0x1E, 0x21, 0x25, 0x28,
       0x2C, 0x2F, 0x33, 0x36, 0x3A, 0x3D, 0x41, 0x44,
       0x48, 0x4B, 0x4F, 0x52, 0x56, 0x59, 0x5C, 0x60,
       0x63, 0x67, 0x6A, 0x6E, 0x71, 0x75, 0x78, 0x7C,
       0x7F, 0x83, 0x86, 0x8A, 0x8D, 0x91, 0x94, 0x98,
       0x9B, 0x9F, 0xA2, 0xA5, 0xA9, 0xAC, 0xB0, 0xB3,
       0xB7, 0xBA, 0xBE, 0xC1, 0xC5, 0xC8, 0xCC, 0xCF,
       0xD3, 0xD6, 0xDA, 0xDD, 0xE1, 0xE4, 0xE8, 0xEB};

 static const uint8_t ulti_chromas[16] =

     { 0x60, 0x67, 0x6D, 0x73, 0x7A, 0x80, 0x86, 0x8D,
       0x93, 0x99, 0xA0, 0xA6, 0xAC, 0xB3, 0xB9, 0xC0};

 /* convert Ultimotion YUV block (sixteen 6-bit Y samples and
  two 4-bit chroma samples) into standard YUV and put it into frame */
 static void ulti_convert_yuv(AVFrame *frame, int x, int y,

                              uint8_t *luma,int chroma)

 {
     uint8_t *y_plane, *cr_plane, *cb_plane;
     int i;

     y_plane = frame->data[0] + x + y * frame->linesize[0];
     cr_plane = frame->data[1] + (x / 4) + (y / 4) * frame->linesize[1];
     cb_plane = frame->data[2] + (x / 4) + (y / 4) * frame->linesize[2];

     cr_plane[0] = ulti_chromas[chroma >> 4];

     cb_plane[0] = ulti_chromas[chroma & 0xF];
 

     for(i = 0; i < 16; i++){

         y_plane[i & 3] = ulti_lumas[luma[i]];
         if((i & 3) == 3) { //next row
             y_plane += frame->linesize[0];
         }

     }
 }
 
 /* generate block like in MS Video1 */
 static void ulti_pattern(AVFrame *frame, int x, int y,

                          int f0, int f1, int Y0, int Y1, int chroma)

 {
     uint8_t Luma[16];
     int mask, i;
     for(mask = 0x80, i = 0; mask; mask >>= 1, i++) {

         if(f0 & mask)
             Luma[i] = Y1;
         else
             Luma[i] = Y0;

     }

     for(mask = 0x80, i = 8; mask; mask >>= 1, i++) {

         if(f1 & mask)
             Luma[i] = Y1;
         else
             Luma[i] = Y0;

     }

     ulti_convert_yuv(frame, x, y, Luma, chroma);
 }
 
 /* fill block with some gradient */
 static void ulti_grad(AVFrame *frame, int x, int y, uint8_t *Y, int chroma, int angle)
 {
     uint8_t Luma[16];
     if(angle & 8) { //reverse order

         int t;
         angle &= 0x7;
         t = Y[0];
         Y[0] = Y[3];
         Y[3] = t;
         t = Y[1];
         Y[1] = Y[2];
         Y[2] = t;

     }
     switch(angle){
     case 0:

         Luma[0]  = Y[0]; Luma[1]  = Y[1]; Luma[2]  = Y[2]; Luma[3]  = Y[3];
         Luma[4]  = Y[0]; Luma[5]  = Y[1]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
         Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[2]; Luma[11] = Y[3];
         Luma[12] = Y[0]; Luma[13] = Y[1]; Luma[14] = Y[2]; Luma[15] = Y[3];
         break;

     case 1:

         Luma[0]  = Y[1]; Luma[1]  = Y[2]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
         Luma[4]  = Y[0]; Luma[5]  = Y[1]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
         Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[2]; Luma[11] = Y[3];
         Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[1]; Luma[15] = Y[2];
         break;

     case 2:

         Luma[0]  = Y[1]; Luma[1]  = Y[2]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
         Luma[4]  = Y[1]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
         Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[2];
         Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[1]; Luma[15] = Y[2];
         break;

     case 3:

         Luma[0]  = Y[2]; Luma[1]  = Y[3]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
         Luma[4]  = Y[1]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[3];
         Luma[8]  = Y[0]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[2];
         Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[1];
         break;

     case 4:

         Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[3]; Luma[3]  = Y[3];
         Luma[4]  = Y[2]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[2];
         Luma[8]  = Y[1]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[1];
         Luma[12] = Y[0]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[0];
         break;

     case 5:

         Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[3]; Luma[3]  = Y[2];
         Luma[4]  = Y[3]; Luma[5]  = Y[2]; Luma[6]  = Y[2]; Luma[7]  = Y[1];
         Luma[8]  = Y[2]; Luma[9]  = Y[1]; Luma[10] = Y[1]; Luma[11] = Y[0];
         Luma[12] = Y[1]; Luma[13] = Y[0]; Luma[14] = Y[0]; Luma[15] = Y[0];
         break;

     case 6:

         Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[2]; Luma[3]  = Y[2];
         Luma[4]  = Y[3]; Luma[5]  = Y[2]; Luma[6]  = Y[1]; Luma[7]  = Y[1];
         Luma[8]  = Y[2]; Luma[9]  = Y[2]; Luma[10] = Y[1]; Luma[11] = Y[0];
         Luma[12] = Y[1]; Luma[13] = Y[1]; Luma[14] = Y[0]; Luma[15] = Y[0];
         break;

     case 7:

         Luma[0]  = Y[3]; Luma[1]  = Y[3]; Luma[2]  = Y[2]; Luma[3]  = Y[1];
         Luma[4]  = Y[3]; Luma[5]  = Y[2]; Luma[6]  = Y[1]; Luma[7]  = Y[0];
         Luma[8]  = Y[3]; Luma[9]  = Y[2]; Luma[10] = Y[1]; Luma[11] = Y[0];
         Luma[12] = Y[2]; Luma[13] = Y[1]; Luma[14] = Y[0]; Luma[15] = Y[0];
         break;

     default:

         Luma[0]  = Y[0]; Luma[1]  = Y[0]; Luma[2]  = Y[1]; Luma[3]  = Y[1];
         Luma[4]  = Y[0]; Luma[5]  = Y[0]; Luma[6]  = Y[1]; Luma[7]  = Y[1];
         Luma[8]  = Y[2]; Luma[9]  = Y[2]; Luma[10] = Y[3]; Luma[11] = Y[3];
         Luma[12] = Y[2]; Luma[13] = Y[2]; Luma[14] = Y[3]; Luma[15] = Y[3];
         break;

     }

     ulti_convert_yuv(frame, x, y, Luma, chroma);
 }
 

 static int ulti_decode_frame(AVCodecContext *avctx,

                              void *data, int *got_frame,

                              AVPacket *avpkt)

 {

     const uint8_t *buf = avpkt->data;
     int buf_size = avpkt->size;

     UltimotionDecodeContext *s=avctx->priv_data;
     int modifier = 0;
     int uniq = 0;
     int mode = 0;
     int blocks = 0;
     int done = 0;
     int x = 0, y = 0;

     int i, ret;

     int skip;
     int tmp;
 

     if ((ret = ff_reget_buffer(avctx, s->frame)) < 0)

         return ret;

     bytestream2_init(&s->gb, buf, buf_size);
 

     while(!done) {

         int idx;
         if(blocks >= s->blocks || y >= s->height)
             break;//all blocks decoded
 

         if (bytestream2_get_bytes_left(&s->gb) < 1)
             goto err;
         idx = bytestream2_get_byteu(&s->gb);

         if((idx & 0xF8) == 0x70) {
             switch(idx) {
             case 0x70: //change modifier

                 modifier = bytestream2_get_byte(&s->gb);

                 if(modifier>1)
                     av_log(avctx, AV_LOG_INFO, "warning: modifier must be 0 or 1, got %i\n", modifier);
                 break;
             case 0x71: // set uniq flag
                 uniq = 1;
                 break;
             case 0x72: //toggle mode
                 mode = !mode;
                 break;
             case 0x73: //end-of-frame
                 done = 1;
                 break;
             case 0x74: //skip some blocks

                 skip = bytestream2_get_byte(&s->gb);

                 if ((blocks + skip) >= s->blocks)
                     break;
                 blocks += skip;
                 x += skip * 8;
                 while(x >= s->width) {
                     x -= s->width;
                     y += 8;
                 }
                 break;
             default:
                 av_log(avctx, AV_LOG_INFO, "warning: unknown escape 0x%02X\n", idx);
             }
         } else { //handle one block
             int code;
             int cf;
             int angle = 0;
             uint8_t Y[4]; // luma samples of block
             int tx = 0, ty = 0; //coords of subblock
             int chroma = 0;
             if (mode || uniq) {
                 uniq = 0;
                 cf = 1;
                 chroma = 0;
             } else {
                 cf = 0;

                 if (idx) {

                     chroma = bytestream2_get_byte(&s->gb);

                 }

             }
             for (i = 0; i < 4; i++) { // for every subblock
                 code = (idx >> (6 - i*2)) & 3; //extract 2 bits
                 if(!code) //skip subblock
                     continue;

                 if(cf) {

                     chroma = bytestream2_get_byte(&s->gb);

                 }

                 tx = x + block_coords[i * 2];
                 ty = y + block_coords[(i * 2) + 1];
                 switch(code) {
                 case 1:

                     tmp = bytestream2_get_byte(&s->gb);

 
                     angle = angle_by_index[(tmp >> 6) & 0x3];
 
                     Y[0] = tmp & 0x3F;
                     Y[1] = Y[0];
 
                     if (angle) {
                         Y[2] = Y[0]+1;
                         if (Y[2] > 0x3F)
                             Y[2] = 0x3F;
                         Y[3] = Y[2];
                     } else {
                         Y[2] = Y[0];
                         Y[3] = Y[0];
                     }
                     break;
 
                 case 2:
                     if (modifier) { // unpack four luma samples

                         tmp = bytestream2_get_be24(&s->gb);

 
                         Y[0] = (tmp >> 18) & 0x3F;
                         Y[1] = (tmp >> 12) & 0x3F;
                         Y[2] = (tmp >> 6) & 0x3F;
                         Y[3] = tmp & 0x3F;
                         angle = 16;
                     } else { // retrieve luma samples from codebook

                         tmp = bytestream2_get_be16(&s->gb);

 
                         angle = (tmp >> 12) & 0xF;
                         tmp &= 0xFFF;
                         tmp <<= 2;
                         Y[0] = s->ulti_codebook[tmp];
                         Y[1] = s->ulti_codebook[tmp + 1];
                         Y[2] = s->ulti_codebook[tmp + 2];
                         Y[3] = s->ulti_codebook[tmp + 3];
                     }
                     break;
 
                 case 3:
                     if (modifier) { // all 16 luma samples
                         uint8_t Luma[16];
 

                         if (bytestream2_get_bytes_left(&s->gb) < 12)
                             goto err;
                         tmp = bytestream2_get_be24u(&s->gb);

                         Luma[0] = (tmp >> 18) & 0x3F;
                         Luma[1] = (tmp >> 12) & 0x3F;
                         Luma[2] = (tmp >> 6) & 0x3F;
                         Luma[3] = tmp & 0x3F;
 

                         tmp = bytestream2_get_be24u(&s->gb);

                         Luma[4] = (tmp >> 18) & 0x3F;
                         Luma[5] = (tmp >> 12) & 0x3F;
                         Luma[6] = (tmp >> 6) & 0x3F;
                         Luma[7] = tmp & 0x3F;
 

                         tmp = bytestream2_get_be24u(&s->gb);

                         Luma[8] = (tmp >> 18) & 0x3F;
                         Luma[9] = (tmp >> 12) & 0x3F;
                         Luma[10] = (tmp >> 6) & 0x3F;
                         Luma[11] = tmp & 0x3F;
 

                         tmp = bytestream2_get_be24u(&s->gb);

                         Luma[12] = (tmp >> 18) & 0x3F;
                         Luma[13] = (tmp >> 12) & 0x3F;
                         Luma[14] = (tmp >> 6) & 0x3F;
                         Luma[15] = tmp & 0x3F;
 

                         ulti_convert_yuv(s->frame, tx, ty, Luma, chroma);

                     } else {

                         if (bytestream2_get_bytes_left(&s->gb) < 4)
                             goto err;
                         tmp = bytestream2_get_byteu(&s->gb);

                         if(tmp & 0x80) {
                             angle = (tmp >> 4) & 0x7;

                             tmp = (tmp << 8) + bytestream2_get_byteu(&s->gb);

                             Y[0] = (tmp >> 6) & 0x3F;
                             Y[1] = tmp & 0x3F;

                             Y[2] = bytestream2_get_byteu(&s->gb) & 0x3F;
                             Y[3] = bytestream2_get_byteu(&s->gb) & 0x3F;

                             ulti_grad(s->frame, tx, ty, Y, chroma, angle); //draw block

                         } else { // some patterns
                             int f0, f1;

                             f0 = bytestream2_get_byteu(&s->gb);

                             f1 = tmp;

                             Y[0] = bytestream2_get_byteu(&s->gb) & 0x3F;
                             Y[1] = bytestream2_get_byteu(&s->gb) & 0x3F;

                             ulti_pattern(s->frame, tx, ty, f1, f0, Y[0], Y[1], chroma);

                         }
                     }
                     break;
                 }
                 if(code != 3)

                     ulti_grad(s->frame, tx, ty, Y, chroma, angle); // draw block

             }
             blocks++;
                 x += 8;
             if(x >= s->width) {
                 x = 0;
                 y += 8;
             }
         }

     }

     *got_frame = 1;

     if ((ret = av_frame_ref(data, s->frame)) < 0)

         return ret;

 
     return buf_size;

 
 err:
     av_log(avctx, AV_LOG_ERROR,
            "Insufficient data\n");
     return AVERROR_INVALIDDATA;

 }
 

 AVCodec ff_ulti_decoder = {

     .name           = "ultimotion",

     .long_name      = NULL_IF_CONFIG_SMALL("IBM UltiMotion"),

     .type           = AVMEDIA_TYPE_VIDEO,

     .id             = AV_CODEC_ID_ULTI,

     .priv_data_size = sizeof(UltimotionDecodeContext),
     .init           = ulti_decode_init,
     .close          = ulti_decode_end,
     .decode         = ulti_decode_frame,
     .capabilities   = CODEC_CAP_DR1,

 };