libavcodec/jpeglsenc.c - third_party/ffmpeg - Git at Google

 /*
  * JPEG-LS encoder
  * Copyright (c) 2003 Michael Niedermayer
  * Copyright (c) 2006 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
  * JPEG-LS encoder.
  */

 #include "avcodec.h"
 #include "get_bits.h"
 #include "put_bits.h"
 #include "golomb.h"
 #include "internal.h"
 #include "mathops.h"
 #include "mjpeg.h"
 #include "mjpegenc.h"
 #include "jpegls.h"

 typedef struct JPEGLSContext {
     AVClass *class;

     int pred;
 } JPEGLSContext;

 /**
  * Encode error from regular symbol
  */
 static inline void ls_encode_regular(JLSState *state, PutBitContext *pb, int Q,
                                      int err)
 {
     int k;
     int val;
     int map;

     for (k = 0; (state->N[Q] << k) < state->A[Q]; k++)
         ;

     map = !state->near && !k && (2 * state->B[Q] <= -state->N[Q]);

     if (err < 0)
         err += state->range;
     if (err >= (state->range + 1 >> 1)) {
         err -= state->range;
         val  = 2 * FFABS(err) - 1 - map;
     } else
         val = 2 * err + map;

     set_ur_golomb_jpegls(pb, val, k, state->limit, state->qbpp);

     ff_jpegls_update_state_regular(state, Q, err);
 }

 /**
  * Encode error from run termination
  */
 static inline void ls_encode_runterm(JLSState *state, PutBitContext *pb,
                                      int RItype, int err, int limit_add)
 {
     int k;
     int val, map;
     int Q = 365 + RItype;
     int temp;

     temp = state->A[Q];
     if (RItype)
         temp += state->N[Q] >> 1;
     for (k = 0; (state->N[Q] << k) < temp; k++)
         ;
     map = 0;
     if (!k && err && (2 * state->B[Q] < state->N[Q]))
         map = 1;

     if (err < 0)
         val = -(2 * err) - 1 - RItype + map;
     else
         val = 2 * err - RItype - map;
     set_ur_golomb_jpegls(pb, val, k, state->limit - limit_add - 1, state->qbpp);

     if (err < 0)
         state->B[Q]++;
     state->A[Q] += (val + 1 - RItype) >> 1;

     ff_jpegls_downscale_state(state, Q);
 }

 /**
  * Encode run value as specified by JPEG-LS standard
  */
 static inline void ls_encode_run(JLSState *state, PutBitContext *pb, int run,
                                  int comp, int trail)
 {
     while (run >= (1 << ff_log2_run[state->run_index[comp]])) {
         put_bits(pb, 1, 1);
         run -= 1 << ff_log2_run[state->run_index[comp]];
         if (state->run_index[comp] < 31)
             state->run_index[comp]++;
     }
     /* if hit EOL, encode another full run, else encode aborted run */
     if (!trail && run) {
         put_bits(pb, 1, 1);
     } else if (trail) {
         put_bits(pb, 1, 0);
         if (ff_log2_run[state->run_index[comp]])
             put_bits(pb, ff_log2_run[state->run_index[comp]], run);
     }
 }

 /**
  * Encode one line of image
  */
 static inline void ls_encode_line(JLSState *state, PutBitContext *pb,
                                   void *last, void *cur, int last2, int w,
                                   int stride, int comp, int bits)
 {
     int x = 0;
     int Ra, Rb, Rc, Rd;
     int D0, D1, D2;

     while (x < w) {
         int err, pred, sign;

         /* compute gradients */
         Ra = x ? R(cur, x - stride) : R(last, x);
         Rb = R(last, x);
         Rc = x ? R(last, x - stride) : last2;
         Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
         D0 = Rd - Rb;
         D1 = Rb - Rc;
         D2 = Rc - Ra;

         /* run mode */
         if ((FFABS(D0) <= state->near) &&
             (FFABS(D1) <= state->near) &&
             (FFABS(D2) <= state->near)) {
             int RUNval, RItype, run;

             run    = 0;
             RUNval = Ra;
             while (x < w && (FFABS(R(cur, x) - RUNval) <= state->near)) {
                 run++;
                 W(cur, x, Ra);
                 x += stride;
             }
             ls_encode_run(state, pb, run, comp, x < w);
             if (x >= w)
                 return;
             Rb     = R(last, x);
             RItype = FFABS(Ra - Rb) <= state->near;
             pred   = RItype ? Ra : Rb;
             err    = R(cur, x) - pred;

             if (!RItype && Ra > Rb)
                 err = -err;

             if (state->near) {
                 if (err > 0)
                     err =  (state->near + err) / state->twonear;
                 else
                     err = -(state->near - err) / state->twonear;

                 if (RItype || (Rb >= Ra))
                     Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
                 else
                     Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
                 W(cur, x, Ra);
             }
             if (err < 0)
                 err += state->range;
             if (err >= state->range + 1 >> 1)
                 err -= state->range;

             ls_encode_runterm(state, pb, RItype, err,
                               ff_log2_run[state->run_index[comp]]);

             if (state->run_index[comp] > 0)
                 state->run_index[comp]--;
         } else { /* regular mode */
             int context;

             context = ff_jpegls_quantize(state, D0) * 81 +
                       ff_jpegls_quantize(state, D1) *  9 +
                       ff_jpegls_quantize(state, D2);
             pred    = mid_pred(Ra, Ra + Rb - Rc, Rb);

             if (context < 0) {
                 context = -context;
                 sign    = 1;
                 pred    = av_clip(pred - state->C[context], 0, state->maxval);
                 err     = pred - R(cur, x);
             } else {
                 sign = 0;
                 pred = av_clip(pred + state->C[context], 0, state->maxval);
                 err  = R(cur, x) - pred;
             }

             if (state->near) {
                 if (err > 0)
                     err =  (state->near + err) / state->twonear;
                 else
                     err = -(state->near - err) / state->twonear;
                 if (!sign)
                     Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
                 else
                     Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
                 W(cur, x, Ra);
             }

             ls_encode_regular(state, pb, context, err);
         }
         x += stride;
     }
 }

 static void ls_store_lse(JLSState *state, PutBitContext *pb)
 {
     /* Test if we have default params and don't need to store LSE */
     JLSState state2 = { 0 };
     state2.bpp  = state->bpp;
     state2.near = state->near;
     ff_jpegls_reset_coding_parameters(&state2, 1);
     if (state->T1 == state2.T1 &&
         state->T2 == state2.T2 &&
         state->T3 == state2.T3 &&
         state->reset == state2.reset)
         return;
     /* store LSE type 1 */
     put_marker(pb, LSE);
     put_bits(pb, 16, 13);
     put_bits(pb, 8, 1);
     put_bits(pb, 16, state->maxval);
     put_bits(pb, 16, state->T1);
     put_bits(pb, 16, state->T2);
     put_bits(pb, 16, state->T3);
     put_bits(pb, 16, state->reset);
 }

 static int encode_picture_ls(AVCodecContext *avctx, AVPacket *pkt,
                              const AVFrame *pict, int *got_packet)
 {
     JPEGLSContext *ctx = avctx->priv_data;
     const AVFrame *const p = pict;
     PutBitContext pb, pb2;
     GetBitContext gb;
     uint8_t *buf2 = NULL;
     uint8_t *zero = NULL;
     uint8_t *cur  = NULL;
     uint8_t *last = NULL;
     JLSState *state = NULL;
     int i, size, ret;
     int comps;

 #if FF_API_PRIVATE_OPT
 FF_DISABLE_DEPRECATION_WARNINGS
     if (avctx->prediction_method)
         ctx->pred = avctx->prediction_method;
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif

     if (avctx->pix_fmt == AV_PIX_FMT_GRAY8 ||
         avctx->pix_fmt == AV_PIX_FMT_GRAY16)
         comps = 1;
     else
         comps = 3;

     if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width  *avctx->height * comps * 4 +
                                 AV_INPUT_BUFFER_MIN_SIZE, 0)) < 0)
         return ret;

     buf2 = av_malloc(pkt->size);
     if (!buf2)
         goto memfail;

     init_put_bits(&pb, pkt->data, pkt->size);
     init_put_bits(&pb2, buf2, pkt->size);

     /* write our own JPEG header, can't use mjpeg_picture_header */
     put_marker(&pb, SOI);
     put_marker(&pb, SOF48);
     put_bits(&pb, 16, 8 + comps * 3); // header size depends on components
     put_bits(&pb, 8, (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8);  // bpp
     put_bits(&pb, 16, avctx->height);
     put_bits(&pb, 16, avctx->width);
     put_bits(&pb, 8, comps);          // components
     for (i = 1; i <= comps; i++) {
         put_bits(&pb, 8, i);     // component ID
         put_bits(&pb, 8, 0x11);  // subsampling: none
         put_bits(&pb, 8, 0);     // Tiq, used by JPEG-LS ext
     }

     put_marker(&pb, SOS);
     put_bits(&pb, 16, 6 + comps * 2);
     put_bits(&pb, 8, comps);
     for (i = 1; i <= comps; i++) {
         put_bits(&pb, 8, i);   // component ID
         put_bits(&pb, 8, 0);   // mapping index: none
     }
     put_bits(&pb, 8, ctx->pred);
     put_bits(&pb, 8, (comps > 1) ? 1 : 0);  // interleaving: 0 - plane, 1 - line
     put_bits(&pb, 8, 0);  // point transform: none

     state = av_mallocz(sizeof(JLSState));
     if (!state)
         goto memfail;

     /* initialize JPEG-LS state from JPEG parameters */
     state->near = ctx->pred;
     state->bpp  = (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8;
     ff_jpegls_reset_coding_parameters(state, 0);
     ff_jpegls_init_state(state);

     ls_store_lse(state, &pb);

     zero = last = av_mallocz(FFABS(p->linesize[0]));
     if (!zero)
         goto memfail;

     cur  = p->data[0];
     if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
         int t = 0;

         for (i = 0; i < avctx->height; i++) {
             ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 8);
             t    = last[0];
             last = cur;
             cur += p->linesize[0];
         }
     } else if (avctx->pix_fmt == AV_PIX_FMT_GRAY16) {
         int t = 0;

         for (i = 0; i < avctx->height; i++) {
             ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 16);
             t    = *((uint16_t *)last);
             last = cur;
             cur += p->linesize[0];
         }
     } else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
         int j, width;
         int Rc[3] = { 0, 0, 0 };

         width = avctx->width * 3;
         for (i = 0; i < avctx->height; i++) {
             for (j = 0; j < 3; j++) {
                 ls_encode_line(state, &pb2, last + j, cur + j, Rc[j],
                                width, 3, j, 8);
                 Rc[j] = last[j];
             }
             last = cur;
             cur += p->linesize[0];
         }
     } else if (avctx->pix_fmt == AV_PIX_FMT_BGR24) {
         int j, width;
         int Rc[3] = { 0, 0, 0 };

         width = avctx->width * 3;
         for (i = 0; i < avctx->height; i++) {
             for (j = 2; j >= 0; j--) {
                 ls_encode_line(state, &pb2, last + j, cur + j, Rc[j],
                                width, 3, j, 8);
                 Rc[j] = last[j];
             }
             last = cur;
             cur += p->linesize[0];
         }
     }

     av_freep(&zero);
     av_freep(&state);

     /* the specification says that after doing 0xff escaping unused bits in
      * the last byte must be set to 0, so just append 7 "optional" zero bits
      * to avoid special-casing. */
     put_bits(&pb2, 7, 0);
     size = put_bits_count(&pb2);
     flush_put_bits(&pb2);
     /* do escape coding */
     init_get_bits(&gb, buf2, size);
     size -= 7;
     while (get_bits_count(&gb) < size) {
         int v;
         v = get_bits(&gb, 8);
         put_bits(&pb, 8, v);
         if (v == 0xFF) {
             v = get_bits(&gb, 7);
             put_bits(&pb, 8, v);
         }
     }
     avpriv_align_put_bits(&pb);
     av_freep(&buf2);

     /* End of image */
     put_marker(&pb, EOI);
     flush_put_bits(&pb);

     emms_c();

     pkt->size   = put_bits_count(&pb) >> 3;
     pkt->flags |= AV_PKT_FLAG_KEY;
     *got_packet = 1;
     return 0;

 memfail:
     av_packet_unref(pkt);
     av_freep(&buf2);
     av_freep(&state);
     av_freep(&zero);
     return AVERROR(ENOMEM);
 }

 static av_cold int encode_init_ls(AVCodecContext *ctx)
 {
 #if FF_API_CODED_FRAME
 FF_DISABLE_DEPRECATION_WARNINGS
     ctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
     ctx->coded_frame->key_frame = 1;
 FF_ENABLE_DEPRECATION_WARNINGS
 #endif

     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) {
         av_log(ctx, AV_LOG_ERROR,
                "Only grayscale and RGB24/BGR24 images are supported\n");
         return -1;
     }
     return 0;
 }

 #define OFFSET(x) offsetof(JPEGLSContext, x)
 #define VE AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {
 { "pred", "Prediction method", OFFSET(pred), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, VE, "pred" },
     { "left",   NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, INT_MIN, INT_MAX, VE, "pred" },
     { "plane",  NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, "pred" },
     { "median", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, "pred" },

     { NULL},
 };

 static const AVClass jpegls_class = {
     .class_name = "jpegls",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };

 AVCodec ff_jpegls_encoder = {
     .name           = "jpegls",
     .long_name      = NULL_IF_CONFIG_SMALL("JPEG-LS"),
     .type           = AVMEDIA_TYPE_VIDEO,
     .id             = AV_CODEC_ID_JPEGLS,
     .priv_data_size = sizeof(JPEGLSContext),
     .priv_class     = &jpegls_class,
     .init           = encode_init_ls,
     .capabilities   = AV_CODEC_CAP_FRAME_THREADS | AV_CODEC_CAP_INTRA_ONLY,
     .encode2        = encode_picture_ls,
     .pix_fmts       = (const enum AVPixelFormat[]) {
         AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB24,
         AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY16,
         AV_PIX_FMT_NONE
     },
     .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
                       FF_CODEC_CAP_INIT_CLEANUP,
 };
	/*
	* JPEG-LS encoder
	* Copyright (c) 2003 Michael Niedermayer
	* Copyright (c) 2006 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
	* JPEG-LS encoder.
	*/

	#include "avcodec.h"
	#include "get_bits.h"
	#include "put_bits.h"
	#include "golomb.h"
	#include "internal.h"
	#include "mathops.h"
	#include "mjpeg.h"
	#include "mjpegenc.h"
	#include "jpegls.h"

	typedef struct JPEGLSContext {
	AVClass *class;

	int pred;
	} JPEGLSContext;

	/**
	* Encode error from regular symbol
	*/
	static inline void ls_encode_regular(JLSState state, PutBitContext pb, int Q,
	int err)
	{
	int k;
	int val;
	int map;

	for (k = 0; (state->N[Q] << k) < state->A[Q]; k++)
	;

	map = !state->near && !k && (2 * state->B[Q] <= -state->N[Q]);

	if (err < 0)
	err += state->range;
	if (err >= (state->range + 1 >> 1)) {
	err -= state->range;
	val = 2 * FFABS(err) - 1 - map;
	} else
	val = 2 * err + map;

	set_ur_golomb_jpegls(pb, val, k, state->limit, state->qbpp);

	ff_jpegls_update_state_regular(state, Q, err);
	}

	/**
	* Encode error from run termination
	*/
	static inline void ls_encode_runterm(JLSState state, PutBitContext pb,
	int RItype, int err, int limit_add)
	{
	int k;
	int val, map;
	int Q = 365 + RItype;
	int temp;

	temp = state->A[Q];
	if (RItype)
	temp += state->N[Q] >> 1;
	for (k = 0; (state->N[Q] << k) < temp; k++)
	;
	map = 0;
	if (!k && err && (2 * state->B[Q] < state->N[Q]))
	map = 1;

	if (err < 0)
	val = -(2 * err) - 1 - RItype + map;
	else
	val = 2 * err - RItype - map;
	set_ur_golomb_jpegls(pb, val, k, state->limit - limit_add - 1, state->qbpp);

	if (err < 0)
	state->B[Q]++;
	state->A[Q] += (val + 1 - RItype) >> 1;

	ff_jpegls_downscale_state(state, Q);
	}

	/**
	* Encode run value as specified by JPEG-LS standard
	*/
	static inline void ls_encode_run(JLSState state, PutBitContext pb, int run,
	int comp, int trail)
	{
	while (run >= (1 << ff_log2_run[state->run_index[comp]])) {
	put_bits(pb, 1, 1);
	run -= 1 << ff_log2_run[state->run_index[comp]];
	if (state->run_index[comp] < 31)
	state->run_index[comp]++;
	}
	/* if hit EOL, encode another full run, else encode aborted run */
	if (!trail && run) {
	put_bits(pb, 1, 1);
	} else if (trail) {
	put_bits(pb, 1, 0);
	if (ff_log2_run[state->run_index[comp]])
	put_bits(pb, ff_log2_run[state->run_index[comp]], run);
	}
	}

	/**
	* Encode one line of image
	*/
	static inline void ls_encode_line(JLSState state, PutBitContext pb,
	void last, void cur, int last2, int w,
	int stride, int comp, int bits)
	{
	int x = 0;
	int Ra, Rb, Rc, Rd;
	int D0, D1, D2;

	while (x < w) {
	int err, pred, sign;

	/* compute gradients */
	Ra = x ? R(cur, x - stride) : R(last, x);
	Rb = R(last, x);
	Rc = x ? R(last, x - stride) : last2;
	Rd = (x >= w - stride) ? R(last, x) : R(last, x + stride);
	D0 = Rd - Rb;
	D1 = Rb - Rc;
	D2 = Rc - Ra;

	/* run mode */
	if ((FFABS(D0) <= state->near) &&
	(FFABS(D1) <= state->near) &&
	(FFABS(D2) <= state->near)) {
	int RUNval, RItype, run;

	run = 0;
	RUNval = Ra;
	while (x < w && (FFABS(R(cur, x) - RUNval) <= state->near)) {
	run++;
	W(cur, x, Ra);
	x += stride;
	}
	ls_encode_run(state, pb, run, comp, x < w);
	if (x >= w)
	return;
	Rb = R(last, x);
	RItype = FFABS(Ra - Rb) <= state->near;
	pred = RItype ? Ra : Rb;
	err = R(cur, x) - pred;

	if (!RItype && Ra > Rb)
	err = -err;

	if (state->near) {
	if (err > 0)
	err = (state->near + err) / state->twonear;
	else
	err = -(state->near - err) / state->twonear;

	if (RItype \|\| (Rb >= Ra))
	Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
	else
	Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
	W(cur, x, Ra);
	}
	if (err < 0)
	err += state->range;
	if (err >= state->range + 1 >> 1)
	err -= state->range;

	ls_encode_runterm(state, pb, RItype, err,
	ff_log2_run[state->run_index[comp]]);

	if (state->run_index[comp] > 0)
	state->run_index[comp]--;
	} else { /* regular mode */
	int context;

	context = ff_jpegls_quantize(state, D0) * 81 +
	ff_jpegls_quantize(state, D1) * 9 +
	ff_jpegls_quantize(state, D2);
	pred = mid_pred(Ra, Ra + Rb - Rc, Rb);

	if (context < 0) {
	context = -context;
	sign = 1;
	pred = av_clip(pred - state->C[context], 0, state->maxval);
	err = pred - R(cur, x);
	} else {
	sign = 0;
	pred = av_clip(pred + state->C[context], 0, state->maxval);
	err = R(cur, x) - pred;
	}

	if (state->near) {
	if (err > 0)
	err = (state->near + err) / state->twonear;
	else
	err = -(state->near - err) / state->twonear;
	if (!sign)
	Ra = av_clip(pred + err * state->twonear, 0, state->maxval);
	else
	Ra = av_clip(pred - err * state->twonear, 0, state->maxval);
	W(cur, x, Ra);
	}

	ls_encode_regular(state, pb, context, err);
	}
	x += stride;
	}
	}

	static void ls_store_lse(JLSState state, PutBitContext pb)
	{
	/* Test if we have default params and don't need to store LSE */
	JLSState state2 = { 0 };
	state2.bpp = state->bpp;
	state2.near = state->near;
	ff_jpegls_reset_coding_parameters(&state2, 1);
	if (state->T1 == state2.T1 &&
	state->T2 == state2.T2 &&
	state->T3 == state2.T3 &&
	state->reset == state2.reset)
	return;
	/* store LSE type 1 */
	put_marker(pb, LSE);
	put_bits(pb, 16, 13);
	put_bits(pb, 8, 1);
	put_bits(pb, 16, state->maxval);
	put_bits(pb, 16, state->T1);
	put_bits(pb, 16, state->T2);
	put_bits(pb, 16, state->T3);
	put_bits(pb, 16, state->reset);
	}

	static int encode_picture_ls(AVCodecContext avctx, AVPacket pkt,
	const AVFrame pict, int got_packet)
	{
	JPEGLSContext *ctx = avctx->priv_data;
	const AVFrame *const p = pict;
	PutBitContext pb, pb2;
	GetBitContext gb;
	uint8_t *buf2 = NULL;
	uint8_t *zero = NULL;
	uint8_t *cur = NULL;
	uint8_t *last = NULL;
	JLSState *state = NULL;
	int i, size, ret;
	int comps;

	#if FF_API_PRIVATE_OPT
	FF_DISABLE_DEPRECATION_WARNINGS
	if (avctx->prediction_method)
	ctx->pred = avctx->prediction_method;
	FF_ENABLE_DEPRECATION_WARNINGS
	#endif

	if (avctx->pix_fmt == AV_PIX_FMT_GRAY8 \|\|
	avctx->pix_fmt == AV_PIX_FMT_GRAY16)
	comps = 1;
	else
	comps = 3;

	if ((ret = ff_alloc_packet2(avctx, pkt, avctx->width avctx->height comps * 4 +
	AV_INPUT_BUFFER_MIN_SIZE, 0)) < 0)
	return ret;

	buf2 = av_malloc(pkt->size);
	if (!buf2)
	goto memfail;

	init_put_bits(&pb, pkt->data, pkt->size);
	init_put_bits(&pb2, buf2, pkt->size);

	/* write our own JPEG header, can't use mjpeg_picture_header */
	put_marker(&pb, SOI);
	put_marker(&pb, SOF48);
	put_bits(&pb, 16, 8 + comps * 3); // header size depends on components
	put_bits(&pb, 8, (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8); // bpp
	put_bits(&pb, 16, avctx->height);
	put_bits(&pb, 16, avctx->width);
	put_bits(&pb, 8, comps); // components
	for (i = 1; i <= comps; i++) {
	put_bits(&pb, 8, i); // component ID
	put_bits(&pb, 8, 0x11); // subsampling: none
	put_bits(&pb, 8, 0); // Tiq, used by JPEG-LS ext
	}

	put_marker(&pb, SOS);
	put_bits(&pb, 16, 6 + comps * 2);
	put_bits(&pb, 8, comps);
	for (i = 1; i <= comps; i++) {
	put_bits(&pb, 8, i); // component ID
	put_bits(&pb, 8, 0); // mapping index: none
	}
	put_bits(&pb, 8, ctx->pred);
	put_bits(&pb, 8, (comps > 1) ? 1 : 0); // interleaving: 0 - plane, 1 - line
	put_bits(&pb, 8, 0); // point transform: none

	state = av_mallocz(sizeof(JLSState));
	if (!state)
	goto memfail;

	/* initialize JPEG-LS state from JPEG parameters */
	state->near = ctx->pred;
	state->bpp = (avctx->pix_fmt == AV_PIX_FMT_GRAY16) ? 16 : 8;
	ff_jpegls_reset_coding_parameters(state, 0);
	ff_jpegls_init_state(state);

	ls_store_lse(state, &pb);

	zero = last = av_mallocz(FFABS(p->linesize[0]));
	if (!zero)
	goto memfail;

	cur = p->data[0];
	if (avctx->pix_fmt == AV_PIX_FMT_GRAY8) {
	int t = 0;

	for (i = 0; i < avctx->height; i++) {
	ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 8);
	t = last[0];
	last = cur;
	cur += p->linesize[0];
	}
	} else if (avctx->pix_fmt == AV_PIX_FMT_GRAY16) {
	int t = 0;

	for (i = 0; i < avctx->height; i++) {
	ls_encode_line(state, &pb2, last, cur, t, avctx->width, 1, 0, 16);
	t = ((uint16_t )last);
	last = cur;
	cur += p->linesize[0];
	}
	} else if (avctx->pix_fmt == AV_PIX_FMT_RGB24) {
	int j, width;
	int Rc[3] = { 0, 0, 0 };

	width = avctx->width * 3;
	for (i = 0; i < avctx->height; i++) {
	for (j = 0; j < 3; j++) {
	ls_encode_line(state, &pb2, last + j, cur + j, Rc[j],
	width, 3, j, 8);
	Rc[j] = last[j];
	}
	last = cur;
	cur += p->linesize[0];
	}
	} else if (avctx->pix_fmt == AV_PIX_FMT_BGR24) {
	int j, width;
	int Rc[3] = { 0, 0, 0 };

	width = avctx->width * 3;
	for (i = 0; i < avctx->height; i++) {
	for (j = 2; j >= 0; j--) {
	ls_encode_line(state, &pb2, last + j, cur + j, Rc[j],
	width, 3, j, 8);
	Rc[j] = last[j];
	}
	last = cur;
	cur += p->linesize[0];
	}
	}

	av_freep(&zero);
	av_freep(&state);

	/* the specification says that after doing 0xff escaping unused bits in
	* the last byte must be set to 0, so just append 7 "optional" zero bits
	* to avoid special-casing. */
	put_bits(&pb2, 7, 0);
	size = put_bits_count(&pb2);
	flush_put_bits(&pb2);
	/* do escape coding */
	init_get_bits(&gb, buf2, size);
	size -= 7;
	while (get_bits_count(&gb) < size) {
	int v;
	v = get_bits(&gb, 8);
	put_bits(&pb, 8, v);
	if (v == 0xFF) {
	v = get_bits(&gb, 7);
	put_bits(&pb, 8, v);
	}
	}
	avpriv_align_put_bits(&pb);
	av_freep(&buf2);

	/* End of image */
	put_marker(&pb, EOI);
	flush_put_bits(&pb);

	emms_c();

	pkt->size = put_bits_count(&pb) >> 3;
	pkt->flags \|= AV_PKT_FLAG_KEY;
	*got_packet = 1;
	return 0;

	memfail:
	av_packet_unref(pkt);
	av_freep(&buf2);
	av_freep(&state);
	av_freep(&zero);
	return AVERROR(ENOMEM);
	}

	static av_cold int encode_init_ls(AVCodecContext *ctx)
	{
	#if FF_API_CODED_FRAME
	FF_DISABLE_DEPRECATION_WARNINGS
	ctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
	ctx->coded_frame->key_frame = 1;
	FF_ENABLE_DEPRECATION_WARNINGS
	#endif

	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) {
	av_log(ctx, AV_LOG_ERROR,
	"Only grayscale and RGB24/BGR24 images are supported\n");
	return -1;
	}
	return 0;
	}

	#define OFFSET(x) offsetof(JPEGLSContext, x)
	#define VE AV_OPT_FLAG_VIDEO_PARAM \| AV_OPT_FLAG_ENCODING_PARAM
	static const AVOption options[] = {
	{ "pred", "Prediction method", OFFSET(pred), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 2, VE, "pred" },
	{ "left", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, INT_MIN, INT_MAX, VE, "pred" },
	{ "plane", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, INT_MIN, INT_MAX, VE, "pred" },
	{ "median", NULL, 0, AV_OPT_TYPE_CONST, { .i64 = 2 }, INT_MIN, INT_MAX, VE, "pred" },

	{ NULL},
	};

	static const AVClass jpegls_class = {
	.class_name = "jpegls",
	.item_name = av_default_item_name,
	.option = options,
	.version = LIBAVUTIL_VERSION_INT,
	};

	AVCodec ff_jpegls_encoder = {
	.name = "jpegls",
	.long_name = NULL_IF_CONFIG_SMALL("JPEG-LS"),
	.type = AVMEDIA_TYPE_VIDEO,
	.id = AV_CODEC_ID_JPEGLS,
	.priv_data_size = sizeof(JPEGLSContext),
	.priv_class = &jpegls_class,
	.init = encode_init_ls,
	.capabilities = AV_CODEC_CAP_FRAME_THREADS \| AV_CODEC_CAP_INTRA_ONLY,
	.encode2 = encode_picture_ls,
	.pix_fmts = (const enum AVPixelFormat[]) {
	AV_PIX_FMT_BGR24, AV_PIX_FMT_RGB24,
	AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY16,
	AV_PIX_FMT_NONE
	},
	.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE \|
	FF_CODEC_CAP_INIT_CLEANUP,
	};