FFmpeg: libavcodec/jpeglsenc.c Source File

00001 /*
00002  * JPEG-LS encoder
00003  * Copyright (c) 2003 Michael Niedermayer
00004  * Copyright (c) 2006 Konstantin Shishkov
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00028 #include "avcodec.h"
00029 #include "get_bits.h"
00030 #include "golomb.h"
00031 #include "internal.h"
00032 #include "mathops.h"
00033 #include "dsputil.h"
00034 #include "mjpeg.h"
00035 #include "jpegls.h"
00036 
00037 
00041 static inline void ls_encode_regular(JLSState *state, PutBitContext *pb, int Q, int err){
00042     int k;
00043     int val;
00044     int map;
00045 
00046     for(k = 0; (state->N[Q] << k) < state->A[Q]; k++);
00047 
00048     map = !state->near && !k && (2 * state->B[Q] <= -state->N[Q]);
00049 
00050     if(err < 0)
00051         err += state->range;
00052     if(err >= ((state->range + 1) >> 1)) {
00053         err -= state->range;
00054         val = 2 * FFABS(err) - 1 - map;
00055     } else
00056         val = 2 * err + map;
00057 
00058     set_ur_golomb_jpegls(pb, val, k, state->limit, state->qbpp);
00059 
00060     ff_jpegls_update_state_regular(state, Q, err);
00061 }
00062 
00066 static inline void ls_encode_runterm(JLSState *state, PutBitContext *pb, int RItype, int err, int limit_add){
00067     int k;
00068     int val, map;
00069     int Q = 365 + RItype;
00070     int temp;
00071 
00072     temp = state->A[Q];
00073     if(RItype)
00074         temp += state->N[Q] >> 1;
00075     for(k = 0; (state->N[Q] << k) < temp; k++);
00076     map = 0;
00077     if(!k && err && (2 * state->B[Q] < state->N[Q]))
00078         map = 1;
00079 
00080     if(err < 0)
00081         val = - (2 * err) - 1 - RItype + map;
00082     else
00083         val = 2 * err - RItype - map;
00084     set_ur_golomb_jpegls(pb, val, k, state->limit - limit_add - 1, state->qbpp);
00085 
00086     if(err < 0)
00087         state->B[Q]++;
00088     state->A[Q] += (val + 1 - RItype) >> 1;
00089 
00090     ff_jpegls_downscale_state(state, Q);
00091 }
00092 
00096 static inline void ls_encode_run(JLSState *state, PutBitContext *pb, int run, int comp, int trail){
00097     while(run >= (1 << ff_log2_run[state->run_index[comp]])){
00098         put_bits(pb, 1, 1);
00099         run -= 1 << ff_log2_run[state->run_index[comp]];
00100         if(state->run_index[comp] < 31)
00101             state->run_index[comp]++;
00102     }
00103     /* if hit EOL, encode another full run, else encode aborted run */
00104     if(!trail && run) {
00105         put_bits(pb, 1, 1);
00106     }else if(trail){
00107         put_bits(pb, 1, 0);
00108         if(ff_log2_run[state->run_index[comp]])
00109             put_bits(pb, ff_log2_run[state->run_index[comp]], run);
00110     }
00111 }
00112 
00116 static inline void ls_encode_line(JLSState *state, PutBitContext *pb, void *last, void *cur, int last2, int w, int stride, int comp, int bits){
00117     int x = 0;
00118     int Ra, Rb, Rc, Rd;
00119     int D0, D1, D2;
00120 
00121     while(x < w) {
00122         int err, pred, sign;
00123 
00124         /* compute gradients */
00125         Ra = x ? R(cur, x - stride) : R(last, x);
00126         Rb = R(last, x);
00127         Rc = x ? R(last, x - stride) : last2;
00128         Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
00129         D0 = Rd - Rb;
00130         D1 = Rb - Rc;
00131         D2 = Rc - Ra;
00132 
00133         /* run mode */
00134         if((FFABS(D0) <= state->near) && (FFABS(D1) <= state->near) && (FFABS(D2) <= state->near)) {
00135             int RUNval, RItype, run;
00136 
00137             run = 0;
00138             RUNval = Ra;
00139             while(x < w && (FFABS(R(cur, x) - RUNval) <= state->near)){
00140                 run++;
00141                 W(cur, x, Ra);
00142                 x += stride;
00143             }
00144             ls_encode_run(state, pb, run, comp, x < w);
00145             if(x >= w)
00146                 return;
00147             Rb = R(last, x);
00148             RItype = (FFABS(Ra - Rb) <= state->near);
00149             pred = RItype ? Ra : Rb;
00150             err = R(cur, x) - pred;
00151 
00152             if(!RItype && Ra > Rb)
00153                 err = -err;
00154 
00155             if(state->near){
00156                 if(err > 0)
00157                     err = (state->near + err) / state->twonear;
00158                 else
00159                     err = -(state->near - err) / state->twonear;
00160 
00161                 if(RItype || (Rb >= Ra))
00162                     Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
00163                 else
00164                     Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
00165                 W(cur, x, Ra);
00166             }
00167             if(err < 0)
00168                 err += state->range;
00169             if(err >= ((state->range + 1) >> 1))
00170                 err -= state->range;
00171 
00172             ls_encode_runterm(state, pb, RItype, err, ff_log2_run[state->run_index[comp]]);
00173 
00174             if(state->run_index[comp] > 0)
00175                 state->run_index[comp]--;
00176         } else { /* regular mode */
00177             int context;
00178 
00179             context = ff_jpegls_quantize(state, D0) * 81 + ff_jpegls_quantize(state, D1) * 9 + ff_jpegls_quantize(state, D2);
00180             pred = mid_pred(Ra, Ra + Rb - Rc, Rb);
00181 
00182             if(context < 0){
00183                 context = -context;
00184                 sign = 1;
00185                 pred = av_clip(pred - state->C[context], 0, state->maxval);
00186                 err = pred - R(cur, x);
00187             }else{
00188                 sign = 0;
00189                 pred = av_clip(pred + state->C[context], 0, state->maxval);
00190                 err = R(cur, x) - pred;
00191             }
00192 
00193             if(state->near){
00194                 if(err > 0)
00195                     err = (state->near + err) / state->twonear;
00196                 else
00197                     err = -(state->near - err) / state->twonear;
00198                 if(!sign)
00199                     Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
00200                 else
00201                     Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
00202                 W(cur, x, Ra);
00203             }
00204 
00205             ls_encode_regular(state, pb, context, err);
00206         }
00207         x += stride;
00208     }
00209 }
00210 
00211 static void ls_store_lse(JLSState *state, PutBitContext *pb){
00212     /* Test if we have default params and don't need to store LSE */
00213     JLSState state2 = { 0 };
00214     state2.bpp = state->bpp;
00215     state2.near = state->near;
00216     ff_jpegls_reset_coding_parameters(&state2, 1);
00217     if(state->T1 == state2.T1 && state->T2 == state2.T2 && state->T3 == state2.T3 && state->reset == state2.reset)
00218         return;
00219     /* store LSE type 1 */
00220     put_marker(pb, LSE);
00221     put_bits(pb, 16, 13);
00222     put_bits(pb, 8,   1);
00223     put_bits(pb, 16, state->maxval);
00224     put_bits(pb, 16, state->T1);
00225     put_bits(pb, 16, state->T2);
00226     put_bits(pb, 16, state->T3);
00227     put_bits(pb, 16, state->reset);
00228 }
00229 
00230 static int encode_picture_ls(AVCodecContext *avctx, AVPacket *pkt,
00231                              const AVFrame *pict, int *got_packet)
00232 {
00233     JpeglsContext * const s = avctx->priv_data;
00234     AVFrame * const p = &s->picture;
00235     const int near = avctx->prediction_method;
00236     PutBitContext pb, pb2;
00237     GetBitContext gb;
00238     uint8_t *buf2, *zero, *cur, *last;
00239     JLSState *state;
00240     int i, size, ret;
00241     int comps;
00242 
00243     *p = *pict;
00244     p->pict_type= AV_PICTURE_TYPE_I;
00245     p->key_frame= 1;
00246 
00247     if(avctx->pix_fmt == AV_PIX_FMT_GRAY8 || avctx->pix_fmt == AV_PIX_FMT_GRAY16)
00248         comps = 1;
00249     else
00250         comps = 3;
00251 
00252     if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width*avctx->height*comps*4 +
00253                                     FF_MIN_BUFFER_SIZE)) < 0)
00254         return ret;
00255 
00256     buf2 = av_malloc(pkt->size);
00257 
00258     init_put_bits(&pb, pkt->data, pkt->size);
00259     init_put_bits(&pb2, buf2, pkt->size);
00260 
00261     /* write our own JPEG header, can't use mjpeg_picture_header */
00262     put_marker(&pb, SOI);
00263     put_marker(&pb, SOF48);
00264     put_bits(&pb, 16, 8 + comps * 3); // header size depends on components
00265     put_bits(&pb,  8, (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8); // bpp
00266     put_bits(&pb, 16, avctx->height);
00267     put_bits(&pb, 16, avctx->width);
00268     put_bits(&pb,  8, comps);         // components
00269     for(i = 1; i <= comps; i++) {
00270         put_bits(&pb,  8, i);    // component ID
00271         put_bits(&pb,  8, 0x11); // subsampling: none
00272         put_bits(&pb,  8, 0);    // Tiq, used by JPEG-LS ext
00273     }
00274 
00275     put_marker(&pb, SOS);
00276     put_bits(&pb, 16, 6 + comps * 2);
00277     put_bits(&pb,  8, comps);
00278     for(i = 1; i <= comps; i++) {
00279         put_bits(&pb,  8, i);  // component ID
00280         put_bits(&pb,  8, 0);  // mapping index: none
00281     }
00282     put_bits(&pb,  8, near);
00283     put_bits(&pb,  8, (comps > 1) ? 1 : 0); // interleaving: 0 - plane, 1 - line
00284     put_bits(&pb,  8, 0); // point transform: none
00285 
00286     state = av_mallocz(sizeof(JLSState));
00287     /* initialize JPEG-LS state from JPEG parameters */
00288     state->near = near;
00289     state->bpp = (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8;
00290     ff_jpegls_reset_coding_parameters(state, 0);
00291     ff_jpegls_init_state(state);
00292 
00293     ls_store_lse(state, &pb);
00294 
00295     zero = av_mallocz(FFABS(p->linesize[0]));
00296     if (!zero) {
00297         av_free(state);
00298         return AVERROR(ENOMEM);
00299     }
00300     last = zero;
00301     cur = p->data[0];
00302     if(avctx->pix_fmt == AV_PIX_FMT_GRAY8){
00303         int t = 0;
00304 
00305         for(i = 0; i < avctx->height; i++) {
00306             ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0,  8);
00307             t = last[0];
00308             last = cur;
00309             cur += p->linesize[0];
00310         }
00311     }else if(avctx->pix_fmt == AV_PIX_FMT_GRAY16){
00312         int t = 0;
00313 
00314         for(i = 0; i < avctx->height; i++) {
00315             ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 16);
00316             t = *((uint16_t*)last);
00317             last = cur;
00318             cur += p->linesize[0];
00319         }
00320     }else if(avctx->pix_fmt == AV_PIX_FMT_RGB24){
00321         int j, width;
00322         int Rc[3] = {0, 0, 0};
00323 
00324         width = avctx->width * 3;
00325         for(i = 0; i < avctx->height; i++) {
00326             for(j = 0; j < 3; j++) {
00327                 ls_encode_line(state, &pb2, last + j, cur + j, Rc[j], width, 3, j, 8);
00328                 Rc[j] = last[j];
00329             }
00330             last = cur;
00331             cur += s->picture.linesize[0];
00332         }
00333     }else if(avctx->pix_fmt == AV_PIX_FMT_BGR24){
00334         int j, width;
00335         int Rc[3] = {0, 0, 0};
00336 
00337         width = avctx->width * 3;
00338         for(i = 0; i < avctx->height; i++) {
00339             for(j = 2; j >= 0; j--) {
00340                 ls_encode_line(state, &pb2, last + j, cur + j, Rc[j], width, 3, j, 8);
00341                 Rc[j] = last[j];
00342             }
00343             last = cur;
00344             cur += s->picture.linesize[0];
00345         }
00346     }
00347 
00348     av_freep(&zero);
00349     av_freep(&state);
00350 
00351     // the specification says that after doing 0xff escaping unused bits in the
00352     // last byte must be set to 0, so just append 7 "optional" zero-bits to
00353     // avoid special-casing.
00354     put_bits(&pb2, 7, 0);
00355     size = put_bits_count(&pb2);
00356     flush_put_bits(&pb2);
00357     /* do escape coding */
00358     init_get_bits(&gb, buf2, size);
00359     size -= 7;
00360     while(get_bits_count(&gb) < size){
00361         int v;
00362         v = get_bits(&gb, 8);
00363         put_bits(&pb, 8, v);
00364         if(v == 0xFF){
00365             v = get_bits(&gb, 7);
00366             put_bits(&pb, 8, v);
00367         }
00368     }
00369     avpriv_align_put_bits(&pb);
00370     av_free(buf2);
00371 
00372     /* End of image */
00373     put_marker(&pb, EOI);
00374     flush_put_bits(&pb);
00375 
00376     emms_c();
00377 
00378     pkt->size   = put_bits_count(&pb) >> 3;
00379     pkt->flags |= AV_PKT_FLAG_KEY;
00380     *got_packet = 1;
00381     return 0;
00382 }
00383 
00384 static av_cold int encode_init_ls(AVCodecContext *ctx) {
00385     JpeglsContext *c = (JpeglsContext*)ctx->priv_data;
00386 
00387     c->avctx = ctx;
00388     ctx->coded_frame = &c->picture;
00389 
00390     if(ctx->pix_fmt != AV_PIX_FMT_GRAY8 && ctx->pix_fmt != AV_PIX_FMT_GRAY16 && ctx->pix_fmt != AV_PIX_FMT_RGB24 && ctx->pix_fmt != AV_PIX_FMT_BGR24){
00391         av_log(ctx, AV_LOG_ERROR, "Only grayscale and RGB24/BGR24 images are supported\n");
00392         return -1;
00393     }
00394     return 0;
00395 }
00396 
00397 AVCodec ff_jpegls_encoder = {
00398     .name           = "jpegls",
00399     .type           = AVMEDIA_TYPE_VIDEO,
00400     .id             = AV_CODEC_ID_JPEGLS,
00401     .priv_data_size = sizeof(JpeglsContext),
00402     .init           = encode_init_ls,
00403     .encode2        = encode_picture_ls,
00404     .pix_fmts       = (const enum AVPixelFormat[]){
00405         AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB24, AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY16,
00406         AV_PIX_FMT_NONE
00407     },
00408     .long_name      = NULL_IF_CONFIG_SMALL("JPEG-LS"),
00409 };