1 /*
2  * JPEG-LS encoder
3  * Copyright (c) 2003 Michael Niedermayer
4  * Copyright (c) 2006 Konstantin Shishkov
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * JPEG-LS encoder.
26  */
27 
28 #define UNCHECKED_BITSTREAM_READER 1
29 #include "libavutil/opt.h"
30 #include "avcodec.h"
31 #include "bytestream.h"
32 #include "codec_internal.h"
33 #include "encode.h"
34 #include "get_bits.h"
35 #include "put_bits.h"
36 #include "put_golomb.h"
37 #include "mathops.h"
38 #include "mjpeg.h"
39 #include "jpegls.h"
40 
41 typedef struct JPEGLSContext {
42     AVClass *class;
43 
44     int pred;
45     int comps;
46 
47     size_t size;
48     uint8_t *buf;
49 } JPEGLSContext;
50 
put_marker_byteu(PutByteContext *pb, enum JpegMarker code)51 static inline void put_marker_byteu(PutByteContext *pb, enum JpegMarker code)
52 {
53     bytestream2_put_byteu(pb, 0xff);
54     bytestream2_put_byteu(pb, code);
55 }
56 
57 /**
58  * Encode error from regular symbol
59  */
ls_encode_regular(JLSState *state, PutBitContext *pb, int Q, int err)60 static inline void ls_encode_regular(JLSState *state, PutBitContext *pb, int Q,
61                                      int err)
62 {
63     int k;
64     int val;
65     int map;
66 
67     for (k = 0; (state->N[Q] << k) < state->A[Q]; k++)
68         ;
69 
70     map = !state->near && !k && (2 * state->B[Q] <= -state->N[Q]);
71 
72     if (err < 0)
73         err += state->range;
74     if (err >= (state->range + 1 >> 1)) {
75         err -= state->range;
76         val  = 2 * FFABS(err) - 1 - map;
77     } else
78         val = 2 * err + map;
79 
80     set_ur_golomb_jpegls(pb, val, k, state->limit, state->qbpp);
81 
82     ff_jpegls_update_state_regular(state, Q, err);
83 }
84 
85 /**
86  * Encode error from run termination
87  */
ls_encode_runterm(JLSState *state, PutBitContext *pb, int RItype, int err, int limit_add)88 static inline void ls_encode_runterm(JLSState *state, PutBitContext *pb,
89                                      int RItype, int err, int limit_add)
90 {
91     int k;
92     int val, map;
93     int Q = 365 + RItype;
94     int temp;
95 
96     temp = state->A[Q];
97     if (RItype)
98         temp += state->N[Q] >> 1;
99     for (k = 0; (state->N[Q] << k) < temp; k++)
100         ;
101     map = 0;
102     if (!k && err && (2 * state->B[Q] < state->N[Q]))
103         map = 1;
104 
105     if (err < 0)
106         val = -(2 * err) - 1 - RItype + map;
107     else
108         val = 2 * err - RItype - map;
109     set_ur_golomb_jpegls(pb, val, k, state->limit - limit_add - 1, state->qbpp);
110 
111     if (err < 0)
112         state->B[Q]++;
113     state->A[Q] += (val + 1 - RItype) >> 1;
114 
115     ff_jpegls_downscale_state(state, Q);
116 }
117 
118 /**
119  * Encode run value as specified by JPEG-LS standard
120  */
ls_encode_run(JLSState *state, PutBitContext *pb, int run, int comp, int trail)121 static inline void ls_encode_run(JLSState *state, PutBitContext *pb, int run,
122                                  int comp, int trail)
123 {
124     while (run >= (1 << ff_log2_run[state->run_index[comp]])) {
125         put_bits(pb, 1, 1);
126         run -= 1 << ff_log2_run[state->run_index[comp]];
127         if (state->run_index[comp] < 31)
128             state->run_index[comp]++;
129     }
130     /* if hit EOL, encode another full run, else encode aborted run */
131     if (!trail && run) {
132         put_bits(pb, 1, 1);
133     } else if (trail) {
134         put_bits(pb, 1, 0);
135         if (ff_log2_run[state->run_index[comp]])
136             put_bits(pb, ff_log2_run[state->run_index[comp]], run);
137     }
138 }
139 
140 /**
141  * Encode one line of image
142  */
ls_encode_line(JLSState *state, PutBitContext *pb, void *tmp, const void *in, int last2, int w, int stride, int comp, int bits)143 static inline void ls_encode_line(JLSState *state, PutBitContext *pb,
144                                   void *tmp, const void *in, int last2, int w,
145                                   int stride, int comp, int bits)
146 {
147     int x = 0;
148     int Ra = R(tmp, 0), Rb, Rc = last2, Rd;
149     int D0, D1, D2;
150 
151     while (x < w) {
152         int err, pred, sign;
153 
154         /* compute gradients */
155         Rb = R(tmp, x);
156         Rd = (x >= w - stride) ? R(tmp, x) : R(tmp, x + stride);
157         D0 = Rd - Rb;
158         D1 = Rb - Rc;
159         D2 = Rc - Ra;
160 
161         /* run mode */
162         if ((FFABS(D0) <= state->near) &&
163             (FFABS(D1) <= state->near) &&
164             (FFABS(D2) <= state->near)) {
165             int RUNval, RItype, run;
166 
167             run    = 0;
168             RUNval = Ra;
169             while (x < w && (FFABS(R(in, x) - RUNval) <= state->near)) {
170                 run++;
171                 W(tmp, x, Ra);
172                 x += stride;
173             }
174             ls_encode_run(state, pb, run, comp, x < w);
175             if (x >= w)
176                 return;
177             Rb     = R(tmp, x);
178             RItype = FFABS(Ra - Rb) <= state->near;
179             pred   = RItype ? Ra : Rb;
180             err    = R(in, x) - pred;
181 
182             if (!RItype && Ra > Rb)
183                 err = -err;
184 
185             if (state->near) {
186                 if (err > 0)
187                     err =  (state->near + err) / state->twonear;
188                 else
189                     err = -(state->near - err) / state->twonear;
190 
191                 if (RItype || (Rb >= Ra))
192                     Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
193                 else
194                     Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
195             } else
196                 Ra = R(in, x);
197             W(tmp, x, Ra);
198 
199             if (err < 0)
200                 err += state->range;
201             if (err >= state->range + 1 >> 1)
202                 err -= state->range;
203 
204             ls_encode_runterm(state, pb, RItype, err,
205                               ff_log2_run[state->run_index[comp]]);
206 
207             if (state->run_index[comp] > 0)
208                 state->run_index[comp]--;
209         } else { /* regular mode */
210             int context;
211 
212             context = ff_jpegls_quantize(state, D0) * 81 +
213                       ff_jpegls_quantize(state, D1) *  9 +
214                       ff_jpegls_quantize(state, D2);
215             pred    = mid_pred(Ra, Ra + Rb - Rc, Rb);
216 
217             if (context < 0) {
218                 context = -context;
219                 sign    = 1;
220                 pred    = av_clip(pred - state->C[context], 0, state->maxval);
221                 err     = pred - R(in, x);
222             } else {
223                 sign = 0;
224                 pred = av_clip(pred + state->C[context], 0, state->maxval);
225                 err  = R(in, x) - pred;
226             }
227 
228             if (state->near) {
229                 if (err > 0)
230                     err =  (state->near + err) / state->twonear;
231                 else
232                     err = -(state->near - err) / state->twonear;
233                 if (!sign)
234                     Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
235                 else
236                     Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
237             } else
238                 Ra = R(in, x);
239             W(tmp, x, Ra);
240 
241             ls_encode_regular(state, pb, context, err);
242         }
243         Rc = Rb;
244         x += stride;
245     }
246 }
247 
ls_store_lse(JLSState *state, PutByteContext *pb)248 static void ls_store_lse(JLSState *state, PutByteContext *pb)
249 {
250     /* Test if we have default params and don't need to store LSE */
251     JLSState state2 = { 0 };
252     state2.bpp  = state->bpp;
253     state2.near = state->near;
254     ff_jpegls_reset_coding_parameters(&state2, 1);
255     if (state->T1 == state2.T1 &&
256         state->T2 == state2.T2 &&
257         state->T3 == state2.T3 &&
258         state->reset == state2.reset)
259         return;
260     /* store LSE type 1 */
261     put_marker_byteu(pb, LSE);
262     bytestream2_put_be16u(pb, 13);
263     bytestream2_put_byteu(pb, 1);
264     bytestream2_put_be16u(pb, state->maxval);
265     bytestream2_put_be16u(pb, state->T1);
266     bytestream2_put_be16u(pb, state->T2);
267     bytestream2_put_be16u(pb, state->T3);
268     bytestream2_put_be16u(pb, state->reset);
269 }
270 
encode_picture_ls(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *pict, int *got_packet)271 static int encode_picture_ls(AVCodecContext *avctx, AVPacket *pkt,
272                              const AVFrame *pict, int *got_packet)
273 {
274     JPEGLSContext *ctx = avctx->priv_data;
275     const AVFrame *const p = pict;
276     PutByteContext pb;
277     PutBitContext pb2;
278     GetBitContext gb;
279     const uint8_t *in;
280     uint8_t *last = NULL;
281     JLSState state = { 0 };
282     size_t size;
283     int i, ret, size_in_bits;
284     int comps;
285 
286     last = av_mallocz(FFABS(p->linesize[0]));
287     if (!last)
288         return AVERROR(ENOMEM);
289 
290     init_put_bits(&pb2, ctx->buf, ctx->size);
291 
292     comps = ctx->comps;
293     /* initialize JPEG-LS state from JPEG parameters */
294     state.near = ctx->pred;
295     state.bpp  = (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8;
296     ff_jpegls_reset_coding_parameters(&state, 0);
297     ff_jpegls_init_state(&state);
298 
299     in = p->data[0];
300     if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
301         int t = 0;
302 
303         for (i = 0; i < avctx->height; i++) {
304             int last0 = last[0];
305             ls_encode_line(&state, &pb2, last, in, t, avctx->width, 1, 0, 8);
306             t   = last0;
307             in += p->linesize[0];
308         }
309     } else if (avctx->pix_fmt == AV_PIX_FMT_GRAY16) {
310         int t = 0;
311 
312         for (i = 0; i < avctx->height; i++) {
313             int last0 = *((uint16_t *)last);
314             ls_encode_line(&state, &pb2, last, in, t, avctx->width, 1, 0, 16);
315             t   = last0;
316             in += p->linesize[0];
317         }
318     } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
319         int j, width;
320         int Rc[3] = { 0, 0, 0 };
321 
322         width = avctx->width * 3;
323         for (i = 0; i < avctx->height; i++) {
324             for (j = 0; j < 3; j++) {
325                 int last0 = last[j];
326                 ls_encode_line(&state, &pb2, last + j, in + j, Rc[j],
327                                width, 3, j, 8);
328                 Rc[j] = last0;
329             }
330             in += p->linesize[0];
331         }
332     } else if (avctx->pix_fmt == AV_PIX_FMT_BGR24) {
333         int j, width;
334         int Rc[3] = { 0, 0, 0 };
335 
336         width = avctx->width * 3;
337         for (i = 0; i < avctx->height; i++) {
338             for (j = 2; j >= 0; j--) {
339                 int last0 = last[j];
340                 ls_encode_line(&state, &pb2, last + j, in + j, Rc[j],
341                                width, 3, j, 8);
342                 Rc[j] = last0;
343             }
344             in += p->linesize[0];
345         }
346     }
347     av_free(last);
348     /* Now the actual image data has been written, which enables us to estimate
349      * the needed packet size: For every 15 input bits, an escape bit might be
350      * added below; and if put_bits_count % 15 is >= 8, then another bit might
351      * be added.
352      * Furthermore the specification says that after doing 0xff escaping unused
353      * bits in the last byte must be set to 0, so just append 7 "optional" zero
354      * bits to avoid special-casing. This also simplifies the size calculation:
355      * Properly rounding up is now automatically baked-in. */
356     put_bits(&pb2, 7, 0);
357     /* Make sure that the bit count + padding is representable in an int;
358        necessary for put_bits_count() as well as for using a GetBitContext. */
359     if (put_bytes_count(&pb2, 0) > INT_MAX / 8 - AV_INPUT_BUFFER_PADDING_SIZE)
360         return AVERROR(ERANGE);
361     size_in_bits = put_bits_count(&pb2);
362     flush_put_bits(&pb2);
363     size  = size_in_bits * 2U / 15;
364     size += 2 + 2 + 2 + 1 + 2 + 2 + 1 + comps * (1 + 1 + 1) + 2 + 2 + 1
365             + comps * (1 + 1) + 1 + 1 + 1; /* Header */
366     size += 2 + 2 + 1 + 2 + 2 + 2 + 2 + 2; /* LSE */
367     size += 2; /* EOI */
368     if ((ret = ff_get_encode_buffer(avctx, pkt, size, 0)) < 0)
369         return ret;
370 
371     bytestream2_init_writer(&pb, pkt->data, pkt->size);
372 
373     /* write our own JPEG header, can't use mjpeg_picture_header */
374     put_marker_byteu(&pb, SOI);
375     put_marker_byteu(&pb, SOF48);
376     bytestream2_put_be16u(&pb, 8 + comps * 3); // header size depends on components
377     bytestream2_put_byteu(&pb, (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8);  // bpp
378     bytestream2_put_be16u(&pb, avctx->height);
379     bytestream2_put_be16u(&pb, avctx->width);
380     bytestream2_put_byteu(&pb, comps);          // components
381     for (i = 1; i <= comps; i++) {
382         bytestream2_put_byteu(&pb, i);     // component ID
383         bytestream2_put_byteu(&pb, 0x11);  // subsampling: none
384         bytestream2_put_byteu(&pb, 0);     // Tiq, used by JPEG-LS ext
385     }
386 
387     put_marker_byteu(&pb, SOS);
388     bytestream2_put_be16u(&pb, 6 + comps * 2);
389     bytestream2_put_byteu(&pb, comps);
390     for (i = 1; i <= comps; i++) {
391         bytestream2_put_byteu(&pb, i);   // component ID
392         bytestream2_put_byteu(&pb, 0);   // mapping index: none
393     }
394     bytestream2_put_byteu(&pb, ctx->pred);
395     bytestream2_put_byteu(&pb, (comps > 1) ? 1 : 0);  // interleaving: 0 - plane, 1 - line
396     bytestream2_put_byteu(&pb, 0);  // point transform: none
397 
398     ls_store_lse(&state, &pb);
399 
400     /* do escape coding */
401     init_get_bits(&gb, pb2.buf, size_in_bits);
402     size_in_bits -= 7;
403     while (get_bits_count(&gb) < size_in_bits) {
404         int v;
405         v = get_bits(&gb, 8);
406         bytestream2_put_byteu(&pb, v);
407         if (v == 0xFF) {
408             v = get_bits(&gb, 7);
409             bytestream2_put_byteu(&pb, v);
410         }
411     }
412 
413     /* End of image */
414     put_marker_byteu(&pb, EOI);
415 
416     emms_c();
417 
418     av_shrink_packet(pkt, bytestream2_tell_p(&pb));
419     *got_packet = 1;
420     return 0;
421 }
422 
encode_jpegls_init(AVCodecContext *avctx)423 static av_cold int encode_jpegls_init(AVCodecContext *avctx)
424 {
425     JPEGLSContext *ctx = avctx->priv_data;
426     size_t size;
427 
428     if ((avctx->width | avctx->height) > UINT16_MAX) {
429         av_log(avctx, AV_LOG_ERROR, "Dimensions exceeding 65535x65535\n");
430         return AVERROR(EINVAL);
431     }
432     if (avctx->pix_fmt == AV_PIX_FMT_GRAY8 ||
433         avctx->pix_fmt == AV_PIX_FMT_GRAY16)
434         ctx->comps = 1;
435     else
436         ctx->comps = 3;
437     size = AV_INPUT_BUFFER_MIN_SIZE;
438     /* INT_MAX due to PutBit-API. */
439     if (avctx->width * (unsigned)avctx->height > (INT_MAX - size) / 4 / ctx->comps)
440         return AVERROR(ERANGE);
441     size += 4 * ctx->comps * avctx->width * avctx->height;
442     ctx->size = size;
443     ctx->buf = av_malloc(size + AV_INPUT_BUFFER_PADDING_SIZE);
444     if (!ctx->buf)
445         return AVERROR(ENOMEM);
446 
447     return 0;
448 }
449 
encode_jpegls_close(AVCodecContext *avctx)450 static av_cold int encode_jpegls_close(AVCodecContext *avctx)
451 {
452     JPEGLSContext *ctx = avctx->priv_data;
453 
454     av_freep(&ctx->buf);
455     return 0;
456 }
457 
458 #define OFFSET(x) offsetof(JPEGLSContext, x)
459 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
460 static const AVOption options[] = {
461 { "pred", "Prediction method", OFFSET(pred), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, VE, "pred" },
462     { "left",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, INT_MIN, INT_MAX, VE, "pred" },
463     { "plane",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, "pred" },
464     { "median", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, "pred" },
465 
466     { NULL},
467 };
468 
469 static const AVClass jpegls_class = {
470     .class_name = "jpegls",
471     .item_name  = av_default_item_name,
472     .option     = options,
473     .version    = LIBAVUTIL_VERSION_INT,
474 };
475 
476 const FFCodec ff_jpegls_encoder = {
477     .p.name         = "jpegls",
478     .p.long_name    = NULL_IF_CONFIG_SMALL("JPEG-LS"),
479     .p.type         = AVMEDIA_TYPE_VIDEO,
480     .p.id           = AV_CODEC_ID_JPEGLS,
481     .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_FRAME_THREADS,
482     .priv_data_size = sizeof(JPEGLSContext),
483     .p.priv_class   = &jpegls_class,
484     .init           = encode_jpegls_init,
485     FF_CODEC_ENCODE_CB(encode_picture_ls),
486     .close          = encode_jpegls_close,
487     .p.pix_fmts     = (const enum AVPixelFormat[]) {
488         AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB24,
489         AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY16,
490         AV_PIX_FMT_NONE
491     },
492     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
493                       FF_CODEC_CAP_INIT_CLEANUP,
494 };
495