yading@10: /*
yading@10:  * LOCO codec
yading@10:  * Copyright (c) 2005 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:  * LOCO codec.
yading@10:  */
yading@10: 
yading@10: #include "avcodec.h"
yading@10: #include "get_bits.h"
yading@10: #include "golomb.h"
yading@10: #include "internal.h"
yading@10: #include "mathops.h"
yading@10: 
yading@10: enum LOCO_MODE {
yading@10:     LOCO_UNKN  =  0,
yading@10:     LOCO_CYUY2 = -1,
yading@10:     LOCO_CRGB  = -2,
yading@10:     LOCO_CRGBA = -3,
yading@10:     LOCO_CYV12 = -4,
yading@10:     LOCO_YUY2  =  1,
yading@10:     LOCO_UYVY  =  2,
yading@10:     LOCO_RGB   =  3,
yading@10:     LOCO_RGBA  =  4,
yading@10:     LOCO_YV12  =  5,
yading@10: };
yading@10: 
yading@10: typedef struct LOCOContext {
yading@10:     AVCodecContext *avctx;
yading@10:     int lossy;
yading@10:     int mode;
yading@10: } LOCOContext;
yading@10: 
yading@10: typedef struct RICEContext {
yading@10:     GetBitContext gb;
yading@10:     int save, run, run2; /* internal rice decoder state */
yading@10:     int sum, count; /* sum and count for getting rice parameter */
yading@10:     int lossy;
yading@10: } RICEContext;
yading@10: 
yading@10: static int loco_get_rice_param(RICEContext *r)
yading@10: {
yading@10:     int cnt = 0;
yading@10:     int val = r->count;
yading@10: 
yading@10:     while (r->sum > val && cnt < 9) {
yading@10:         val <<= 1;
yading@10:         cnt++;
yading@10:     }
yading@10: 
yading@10:     return cnt;
yading@10: }
yading@10: 
yading@10: static inline void loco_update_rice_param(RICEContext *r, int val)
yading@10: {
yading@10:     r->sum += val;
yading@10:     r->count++;
yading@10: 
yading@10:     if (r->count == 16) {
yading@10:         r->sum   >>= 1;
yading@10:         r->count >>= 1;
yading@10:     }
yading@10: }
yading@10: 
yading@10: static inline int loco_get_rice(RICEContext *r)
yading@10: {
yading@10:     int v;
yading@10:     if (r->run > 0) { /* we have zero run */
yading@10:         r->run--;
yading@10:         loco_update_rice_param(r, 0);
yading@10:         return 0;
yading@10:     }
yading@10:     v = get_ur_golomb_jpegls(&r->gb, loco_get_rice_param(r), INT_MAX, 0);
yading@10:     loco_update_rice_param(r, (v + 1) >> 1);
yading@10:     if (!v) {
yading@10:         if (r->save >= 0) {
yading@10:             r->run = get_ur_golomb_jpegls(&r->gb, 2, INT_MAX, 0);
yading@10:             if (r->run > 1)
yading@10:                 r->save += r->run + 1;
yading@10:             else
yading@10:                 r->save -= 3;
yading@10:         } else
yading@10:             r->run2++;
yading@10:     } else {
yading@10:         v = ((v >> 1) + r->lossy) ^ -(v & 1);
yading@10:         if (r->run2 > 0) {
yading@10:             if (r->run2 > 2)
yading@10:                 r->save += r->run2;
yading@10:             else
yading@10:                 r->save -= 3;
yading@10:             r->run2 = 0;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     return v;
yading@10: }
yading@10: 
yading@10: /* LOCO main predictor - LOCO-I/JPEG-LS predictor */
yading@10: static inline int loco_predict(uint8_t* data, int stride, int step)
yading@10: {
yading@10:     int a, b, c;
yading@10: 
yading@10:     a = data[-stride];
yading@10:     b = data[-step];
yading@10:     c = data[-stride - step];
yading@10: 
yading@10:     return mid_pred(a, a + b - c, b);
yading@10: }
yading@10: 
yading@10: static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
yading@10:                              int stride, const uint8_t *buf, int buf_size, int step)
yading@10: {
yading@10:     RICEContext rc;
yading@10:     int val;
yading@10:     int i, j;
yading@10: 
yading@10:     if(buf_size<=0)
yading@10:         return -1;
yading@10: 
yading@10:     init_get_bits(&rc.gb, buf, buf_size*8);
yading@10:     rc.save  = 0;
yading@10:     rc.run   = 0;
yading@10:     rc.run2  = 0;
yading@10:     rc.lossy = l->lossy;
yading@10: 
yading@10:     rc.sum   = 8;
yading@10:     rc.count = 1;
yading@10: 
yading@10:     /* restore top left pixel */
yading@10:     val     = loco_get_rice(&rc);
yading@10:     data[0] = 128 + val;
yading@10:     /* restore top line */
yading@10:     for (i = 1; i < width; i++) {
yading@10:         val = loco_get_rice(&rc);
yading@10:         data[i * step] = data[i * step - step] + val;
yading@10:     }
yading@10:     data += stride;
yading@10:     for (j = 1; j < height; j++) {
yading@10:         /* restore left column */
yading@10:         val = loco_get_rice(&rc);
yading@10:         data[0] = data[-stride] + val;
yading@10:         /* restore all other pixels */
yading@10:         for (i = 1; i < width; i++) {
yading@10:             val = loco_get_rice(&rc);
yading@10:             data[i * step] = loco_predict(&data[i * step], stride, step) + val;
yading@10:         }
yading@10:         data += stride;
yading@10:     }
yading@10: 
yading@10:     return (get_bits_count(&rc.gb) + 7) >> 3;
yading@10: }
yading@10: 
yading@10: static int decode_frame(AVCodecContext *avctx,
yading@10:                         void *data, int *got_frame,
yading@10:                         AVPacket *avpkt)
yading@10: {
yading@10:     LOCOContext * const l = avctx->priv_data;
yading@10:     const uint8_t *buf    = avpkt->data;
yading@10:     int buf_size          = avpkt->size;
yading@10:     AVFrame * const p     = data;
yading@10:     int decoded, ret;
yading@10: 
yading@10:     if ((ret = ff_get_buffer(avctx, p, 0)) < 0)
yading@10:         return ret;
yading@10:     p->key_frame = 1;
yading@10: 
yading@10: #define ADVANCE_BY_DECODED do { \
yading@10:     if (decoded < 0 || decoded >= buf_size) goto buf_too_small; \
yading@10:     buf += decoded; buf_size -= decoded; \
yading@10: } while(0)
yading@10:     switch(l->mode) {
yading@10:     case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
yading@10:         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
yading@10:                                     p->linesize[0], buf, buf_size, 1);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
yading@10:                                     p->linesize[1], buf, buf_size, 1);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
yading@10:                                     p->linesize[2], buf, buf_size, 1);
yading@10:         break;
yading@10:     case LOCO_CYV12: case LOCO_YV12:
yading@10:         decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
yading@10:                                     p->linesize[0], buf, buf_size, 1);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
yading@10:                                     p->linesize[2], buf, buf_size, 1);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
yading@10:                                     p->linesize[1], buf, buf_size, 1);
yading@10:         break;
yading@10:     case LOCO_CRGB: case LOCO_RGB:
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 3);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 3);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 3);
yading@10:         break;
yading@10:     case LOCO_CRGBA:
yading@10:     case LOCO_RGBA:
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1), avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 4);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 1, avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 4);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 2, avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 4);
yading@10:         ADVANCE_BY_DECODED;
yading@10:         decoded = loco_decode_plane(l, p->data[0] + p->linesize[0]*(avctx->height-1) + 3, avctx->width, avctx->height,
yading@10:                                     -p->linesize[0], buf, buf_size, 4);
yading@10:         break;
yading@10:     default:
yading@10:         av_assert0(0);
yading@10:     }
yading@10: 
yading@10:     if (decoded < 0 || decoded > buf_size)
yading@10:         goto buf_too_small;
yading@10:     buf_size -= decoded;
yading@10: 
yading@10:     *got_frame      = 1;
yading@10: 
yading@10:     return avpkt->size - buf_size;
yading@10: buf_too_small:
yading@10:     av_log(avctx, AV_LOG_ERROR, "Input data too small.\n");
yading@10:     return AVERROR(EINVAL);
yading@10: }
yading@10: 
yading@10: static av_cold int decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     LOCOContext * const l = avctx->priv_data;
yading@10:     int version;
yading@10: 
yading@10:     l->avctx = avctx;
yading@10:     if (avctx->extradata_size < 12) {
yading@10:         av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
yading@10:                avctx->extradata_size);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     version = AV_RL32(avctx->extradata);
yading@10:     switch (version) {
yading@10:     case 1:
yading@10:         l->lossy = 0;
yading@10:         break;
yading@10:     case 2:
yading@10:         l->lossy = AV_RL32(avctx->extradata + 8);
yading@10:         break;
yading@10:     default:
yading@10:         l->lossy = AV_RL32(avctx->extradata + 8);
yading@10:         avpriv_request_sample(avctx, "LOCO codec version %i", version);
yading@10:     }
yading@10: 
yading@10:     l->mode = AV_RL32(avctx->extradata + 4);
yading@10:     switch (l->mode) {
yading@10:     case LOCO_CYUY2:
yading@10:     case LOCO_YUY2:
yading@10:     case LOCO_UYVY:
yading@10:         avctx->pix_fmt = AV_PIX_FMT_YUV422P;
yading@10:         break;
yading@10:     case LOCO_CRGB:
yading@10:     case LOCO_RGB:
yading@10:         avctx->pix_fmt = AV_PIX_FMT_BGR24;
yading@10:         break;
yading@10:     case LOCO_CYV12:
yading@10:     case LOCO_YV12:
yading@10:         avctx->pix_fmt = AV_PIX_FMT_YUV420P;
yading@10:         break;
yading@10:     case LOCO_CRGBA:
yading@10:     case LOCO_RGBA:
yading@10:         avctx->pix_fmt = AV_PIX_FMT_BGRA;
yading@10:         break;
yading@10:     default:
yading@10:         av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
yading@10:         return AVERROR_INVALIDDATA;
yading@10:     }
yading@10:     if (avctx->debug & FF_DEBUG_PICT_INFO)
yading@10:         av_log(avctx, AV_LOG_INFO, "lossy:%i, version:%i, mode: %i\n", l->lossy, version, l->mode);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_loco_decoder = {
yading@10:     .name           = "loco",
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_LOCO,
yading@10:     .priv_data_size = sizeof(LOCOContext),
yading@10:     .init           = decode_init,
yading@10:     .decode         = decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("LOCO"),
yading@10: };