yading@10: /*
yading@10:  * JPEG-LS decoder
yading@10:  * Copyright (c) 2003 Michael Niedermayer
yading@10:  * Copyright (c) 2006 Konstantin Shishkov
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * JPEG-LS decoder.
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "get_bits.h"
yading@10: #include "golomb.h"
yading@10: #include "mathops.h"
yading@10: #include "mjpeg.h"
yading@10: #include "mjpegdec.h"
yading@10: #include "jpegls.h"
yading@10: #include "jpeglsdec.h"
yading@10: 
yading@10: 
yading@10: /*
yading@10: * Uncomment this to significantly speed up decoding of broken JPEG-LS
yading@10: * (or test broken JPEG-LS decoder) and slow down ordinary decoding a bit.
yading@10: *
yading@10: * There is no Golomb code with length >= 32 bits possible, so check and
yading@10: * avoid situation of 32 zeros, FFmpeg Golomb decoder is painfully slow
yading@10: * on this errors.
yading@10: */
yading@10: //#define JLS_BROKEN
yading@10: 
yading@10: 
yading@10: /**
yading@10:  * Decode LSE block with initialization parameters
yading@10:  */
yading@10: int ff_jpegls_decode_lse(MJpegDecodeContext *s)
yading@10: {
yading@10:     int id;
yading@10: 
yading@10:     skip_bits(&s->gb, 16);  /* length: FIXME: verify field validity */
yading@10:     id = get_bits(&s->gb, 8);
yading@10: 
yading@10:     switch(id){
yading@10:     case 1:
yading@10:         s->maxval= get_bits(&s->gb, 16);
yading@10:         s->t1= get_bits(&s->gb, 16);
yading@10:         s->t2= get_bits(&s->gb, 16);
yading@10:         s->t3= get_bits(&s->gb, 16);
yading@10:         s->reset= get_bits(&s->gb, 16);
yading@10: 
yading@10: //        ff_jpegls_reset_coding_parameters(s, 0);
yading@10:         //FIXME quant table?
yading@10:         break;
yading@10:     case 2:
yading@10:     case 3:
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "palette not supported\n");
yading@10:         return -1;
yading@10:     case 4:
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "oversize image not supported\n");
yading@10:         return -1;
yading@10:     default:
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "invalid id %d\n", id);
yading@10:         return -1;
yading@10:     }
yading@10:     av_dlog(s->avctx, "ID=%i, T=%i,%i,%i\n", id, s->t1, s->t2, s->t3);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Get context-dependent Golomb code, decode it and update context
yading@10:  */
yading@10: static inline int ls_get_code_regular(GetBitContext *gb, JLSState *state, int Q){
yading@10:     int k, ret;
yading@10: 
yading@10:     for(k = 0; (state->N[Q] << k) < state->A[Q]; k++);
yading@10: 
yading@10: #ifdef JLS_BROKEN
yading@10:     if(!show_bits_long(gb, 32))return -1;
yading@10: #endif
yading@10:     ret = get_ur_golomb_jpegls(gb, k, state->limit, state->qbpp);
yading@10: 
yading@10:     /* decode mapped error */
yading@10:     if(ret & 1)
yading@10:         ret = -((ret + 1) >> 1);
yading@10:     else
yading@10:         ret >>= 1;
yading@10: 
yading@10:     /* for NEAR=0, k=0 and 2*B[Q] <= - N[Q] mapping is reversed */
yading@10:     if(!state->near && !k && (2 * state->B[Q] <= -state->N[Q]))
yading@10:         ret = -(ret + 1);
yading@10: 
yading@10:     ret= ff_jpegls_update_state_regular(state, Q, ret);
yading@10: 
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Get Golomb code, decode it and update state for run termination
yading@10:  */
yading@10: static inline int ls_get_code_runterm(GetBitContext *gb, JLSState *state, int RItype, int limit_add){
yading@10:     int k, ret, temp, map;
yading@10:     int Q = 365 + RItype;
yading@10: 
yading@10:     temp=  state->A[Q];
yading@10:     if(RItype)
yading@10:         temp += state->N[Q] >> 1;
yading@10: 
yading@10:     for(k = 0; (state->N[Q] << k) < temp; k++);
yading@10: 
yading@10: #ifdef JLS_BROKEN
yading@10:     if(!show_bits_long(gb, 32))return -1;
yading@10: #endif
yading@10:     ret = get_ur_golomb_jpegls(gb, k, state->limit - limit_add - 1, state->qbpp);
yading@10: 
yading@10:     /* decode mapped error */
yading@10:     map = 0;
yading@10:     if(!k && (RItype || ret) && (2 * state->B[Q] < state->N[Q]))
yading@10:         map = 1;
yading@10:     ret += RItype + map;
yading@10: 
yading@10:     if(ret & 1){
yading@10:         ret = map - ((ret + 1) >> 1);
yading@10:         state->B[Q]++;
yading@10:     } else {
yading@10:         ret = ret >> 1;
yading@10:     }
yading@10: 
yading@10:     /* update state */
yading@10:     state->A[Q] += FFABS(ret) - RItype;
yading@10:     ret *= state->twonear;
yading@10:     ff_jpegls_downscale_state(state, Q);
yading@10: 
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: /**
yading@10:  * Decode one line of image
yading@10:  */
yading@10: static inline void ls_decode_line(JLSState *state, MJpegDecodeContext *s, void *last, void *dst, int last2, int w, int stride, int comp, int bits){
yading@10:     int i, x = 0;
yading@10:     int Ra, Rb, Rc, Rd;
yading@10:     int D0, D1, D2;
yading@10: 
yading@10:     while(x < w) {
yading@10:         int err, pred;
yading@10: 
yading@10:         /* compute gradients */
yading@10:         Ra = x ? R(dst, x - stride) : R(last, x);
yading@10:         Rb = R(last, x);
yading@10:         Rc = x ? R(last, x - stride) : last2;
yading@10:         Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
yading@10:         D0 = Rd - Rb;
yading@10:         D1 = Rb - Rc;
yading@10:         D2 = Rc - Ra;
yading@10:         /* run mode */
yading@10:         if((FFABS(D0) <= state->near) && (FFABS(D1) <= state->near) && (FFABS(D2) <= state->near)) {
yading@10:             int r;
yading@10:             int RItype;
yading@10: 
yading@10:             /* decode full runs while available */
yading@10:             while(get_bits1(&s->gb)) {
yading@10:                 int r;
yading@10:                 r = 1 << ff_log2_run[state->run_index[comp]];
yading@10:                 if(x + r * stride > w) {
yading@10:                     r = (w - x) / stride;
yading@10:                 }
yading@10:                 for(i = 0; i < r; i++) {
yading@10:                     W(dst, x, Ra);
yading@10:                     x += stride;
yading@10:                 }
yading@10:                 /* if EOL reached, we stop decoding */
yading@10:                 if(r != (1 << ff_log2_run[state->run_index[comp]]))
yading@10:                     return;
yading@10:                 if(state->run_index[comp] < 31)
yading@10:                     state->run_index[comp]++;
yading@10:                 if(x + stride > w)
yading@10:                     return;
yading@10:             }
yading@10:             /* decode aborted run */
yading@10:             r = ff_log2_run[state->run_index[comp]];
yading@10:             if(r)
yading@10:                 r = get_bits_long(&s->gb, r);
yading@10:             if(x + r * stride > w) {
yading@10:                 r = (w - x) / stride;
yading@10:             }
yading@10:             for(i = 0; i < r; i++) {
yading@10:                 W(dst, x, Ra);
yading@10:                 x += stride;
yading@10:             }
yading@10: 
yading@10:             /* decode run termination value */
yading@10:             Rb = R(last, x);
yading@10:             RItype = (FFABS(Ra - Rb) <= state->near) ? 1 : 0;
yading@10:             err = ls_get_code_runterm(&s->gb, state, RItype, ff_log2_run[state->run_index[comp]]);
yading@10:             if(state->run_index[comp])
yading@10:                 state->run_index[comp]--;
yading@10: 
yading@10:             if(state->near && RItype){
yading@10:                 pred = Ra + err;
yading@10:             } else {
yading@10:                 if(Rb < Ra)
yading@10:                     pred = Rb - err;
yading@10:                 else
yading@10:                     pred = Rb + err;
yading@10:             }
yading@10:         } else { /* regular mode */
yading@10:             int context, sign;
yading@10: 
yading@10:             context = ff_jpegls_quantize(state, D0) * 81 + ff_jpegls_quantize(state, D1) * 9 + ff_jpegls_quantize(state, D2);
yading@10:             pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
yading@10: 
yading@10:             if(context < 0){
yading@10:                 context = -context;
yading@10:                 sign = 1;
yading@10:             }else{
yading@10:                 sign = 0;
yading@10:             }
yading@10: 
yading@10:             if(sign){
yading@10:                 pred = av_clip(pred - state->C[context], 0, state->maxval);
yading@10:                 err = -ls_get_code_regular(&s->gb, state, context);
yading@10:             } else {
yading@10:                 pred = av_clip(pred + state->C[context], 0, state->maxval);
yading@10:                 err = ls_get_code_regular(&s->gb, state, context);
yading@10:             }
yading@10: 
yading@10:             /* we have to do something more for near-lossless coding */
yading@10:             pred += err;
yading@10:         }
yading@10:         if(state->near){
yading@10:             if(pred < -state->near)
yading@10:                 pred += state->range * state->twonear;
yading@10:             else if(pred > state->maxval + state->near)
yading@10:                 pred -= state->range * state->twonear;
yading@10:             pred = av_clip(pred, 0, state->maxval);
yading@10:         }
yading@10: 
yading@10:         pred &= state->maxval;
yading@10:         W(dst, x, pred);
yading@10:         x += stride;
yading@10:     }
yading@10: }
yading@10: 
yading@10: int ff_jpegls_decode_picture(MJpegDecodeContext *s, int near, int point_transform, int ilv){
yading@10:     int i, t = 0;
yading@10:     uint8_t *zero, *last, *cur;
yading@10:     JLSState *state;
yading@10:     int off = 0, stride = 1, width, shift;
yading@10: 
yading@10:     zero = av_mallocz(s->picture.linesize[0]);
yading@10:     last = zero;
yading@10:     cur = s->picture.data[0];
yading@10: 
yading@10:     state = av_mallocz(sizeof(JLSState));
yading@10:     /* initialize JPEG-LS state from JPEG parameters */
yading@10:     state->near = near;
yading@10:     state->bpp = (s->bits < 2) ? 2 : s->bits;
yading@10:     state->maxval = s->maxval;
yading@10:     state->T1 = s->t1;
yading@10:     state->T2 = s->t2;
yading@10:     state->T3 = s->t3;
yading@10:     state->reset = s->reset;
yading@10:     ff_jpegls_reset_coding_parameters(state, 0);
yading@10:     ff_jpegls_init_state(state);
yading@10: 
yading@10:     if(s->bits <= 8)
yading@10:         shift = point_transform + (8 - s->bits);
yading@10:     else
yading@10:         shift = point_transform + (16 - s->bits);
yading@10: 
yading@10:     if (s->avctx->debug & FF_DEBUG_PICT_INFO) {
yading@10:         av_log(s->avctx, AV_LOG_DEBUG, "JPEG-LS params: %ix%i NEAR=%i MV=%i T(%i,%i,%i) RESET=%i, LIMIT=%i, qbpp=%i, RANGE=%i\n",
yading@10:                 s->width, s->height, state->near, state->maxval,
yading@10:                 state->T1, state->T2, state->T3,
yading@10:                 state->reset, state->limit, state->qbpp, state->range);
yading@10:         av_log(s->avctx, AV_LOG_DEBUG, "JPEG params: ILV=%i Pt=%i BPP=%i, scan = %i\n",
yading@10:                 ilv, point_transform, s->bits, s->cur_scan);
yading@10:     }
yading@10:     if(ilv == 0) { /* separate planes */
yading@10:         stride = (s->nb_components > 1) ? 3 : 1;
yading@10:         off = av_clip(s->cur_scan - 1, 0, stride - 1);
yading@10:         width = s->width * stride;
yading@10:         cur += off;
yading@10:         for(i = 0; i < s->height; i++) {
yading@10:             if(s->bits <= 8){
yading@10:                 ls_decode_line(state, s, last, cur, t, width, stride, off,  8);
yading@10:                 t = last[0];
yading@10:             }else{
yading@10:                 ls_decode_line(state, s, last, cur, t, width, stride, off, 16);
yading@10:                 t = *((uint16_t*)last);
yading@10:             }
yading@10:             last = cur;
yading@10:             cur += s->picture.linesize[0];
yading@10: 
yading@10:             if (s->restart_interval && !--s->restart_count) {
yading@10:                 align_get_bits(&s->gb);
yading@10:                 skip_bits(&s->gb, 16); /* skip RSTn */
yading@10:             }
yading@10:         }
yading@10:     } else if(ilv == 1) { /* line interleaving */
yading@10:         int j;
yading@10:         int Rc[3] = {0, 0, 0};
yading@10:         stride = (s->nb_components > 1) ? 3 : 1;
yading@10:         memset(cur, 0, s->picture.linesize[0]);
yading@10:         width = s->width * stride;
yading@10:         for(i = 0; i < s->height; i++) {
yading@10:             for(j = 0; j < stride; j++) {
yading@10:                 ls_decode_line(state, s, last + j, cur + j, Rc[j], width, stride, j, 8);
yading@10:                 Rc[j] = last[j];
yading@10: 
yading@10:                 if (s->restart_interval && !--s->restart_count) {
yading@10:                     align_get_bits(&s->gb);
yading@10:                     skip_bits(&s->gb, 16); /* skip RSTn */
yading@10:                 }
yading@10:             }
yading@10:             last = cur;
yading@10:             cur += s->picture.linesize[0];
yading@10:         }
yading@10:     } else if(ilv == 2) { /* sample interleaving */
yading@10:         av_log(s->avctx, AV_LOG_ERROR, "Sample interleaved images are not supported.\n");
yading@10:         av_free(state);
yading@10:         av_free(zero);
yading@10:         return -1;
yading@10:     }
yading@10: 
yading@10:     if(shift){ /* we need to do point transform or normalize samples */
yading@10:         int x, w;
yading@10: 
yading@10:         w = s->width * s->nb_components;
yading@10: 
yading@10:         if(s->bits <= 8){
yading@10:             uint8_t *src = s->picture.data[0];
yading@10: 
yading@10:             for(i = 0; i < s->height; i++){
yading@10:                 for(x = off; x < w; x+= stride){
yading@10:                     src[x] <<= shift;
yading@10:                 }
yading@10:                 src += s->picture.linesize[0];
yading@10:             }
yading@10:         }else{
yading@10:             uint16_t *src = (uint16_t*) s->picture.data[0];
yading@10: 
yading@10:             for(i = 0; i < s->height; i++){
yading@10:                 for(x = 0; x < w; x++){
yading@10:                     src[x] <<= shift;
yading@10:                 }
yading@10:                 src += s->picture.linesize[0]/2;
yading@10:             }
yading@10:         }
yading@10:     }
yading@10:     av_free(state);
yading@10:     av_free(zero);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: 
yading@10: AVCodec ff_jpegls_decoder = {
yading@10:     .name           = "jpegls",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_JPEGLS,
yading@10:     .priv_data_size = sizeof(MJpegDecodeContext),
yading@10:     .init           = ff_mjpeg_decode_init,
yading@10:     .close          = ff_mjpeg_decode_end,
yading@10:     .decode         = ff_mjpeg_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("JPEG-LS"),
yading@10: };