--- /dev/null
+/*
+ * LOCO codec
+ * Copyright (c) 2005 Konstantin Shishkov
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/**
+ * @file loco.c
+ * LOCO codec.
+ */
+
+#include "avcodec.h"
+#include "common.h"
+#include "bitstream.h"
+#include "golomb.h"
+
+enum LOCO_MODE {LOCO_UNKN=0, LOCO_CYUY2=-1, LOCO_CRGB=-2, LOCO_CYV12=-3,
+ LOCO_YUY2=1, LOCO_UYVY=2, LOCO_RGB=3, LOCO_RGBA=4, LOCO_YV12=5};
+
+typedef struct LOCOContext{
+ AVCodecContext *avctx;
+ AVFrame pic;
+ int lossy;
+ int mode;
+} LOCOContext;
+
+typedef struct RICEContext{
+ GetBitContext gb;
+ int save, run, run2; /* internal rice decoder state */
+ int sum, count; /* sum and count for getting rice parameter */
+}RICEContext;
+
+/* could use get_sr_golomb() but is behaves differently on numbers like Rice(2, -64) */
+static inline int get_rice(GetBitContext *gb, int K)
+{
+ int i;
+ int V = 0;
+ for(i = 0; !get_bits1(gb); i++);
+ V = i;
+ for(i = 0; i < K; i++) V = (V << 1) | get_bits1(gb);
+ if(V & 1) return (V + 1) >> 1;
+ return -(V >> 1);
+}
+
+static inline int get_u_rice(GetBitContext *gb, int K)
+{
+ int i;
+ int V = 0;
+ for(i = 0; !get_bits1(gb); i++);
+ V = i;
+ for(i = 0; i < K; i++) V = (V << 1) | get_bits1(gb);
+ return V;
+}
+
+static int loco_get_rice_param(RICEContext *r)
+{
+ int cnt = 0;
+ int val = r->count;
+
+ while(r->sum > val && cnt < 9) {
+ val <<= 1;
+ cnt++;
+ }
+
+ return cnt;
+}
+
+static inline void loco_update_rice_param(RICEContext *r, int val)
+{
+ if (val < 0)
+ val = -val;
+ r->sum += val;
+ r->count++;
+
+ if(r->count == 16) {
+ r->sum >>= 1;
+ r->count >>= 1;
+ }
+}
+
+static inline int loco_get_rice(RICEContext *r)
+{
+ int v;
+
+ if (r->run > 0) { /* we have zero run */
+ r->run--;
+ return 0;
+ }
+ v = -get_rice(&r->gb, loco_get_rice_param(r));
+ if (!v) {
+ if (r->save >= 0) {
+ r->run = get_u_rice(&r->gb, 2);
+ if(r->run > 1)
+ r->save += r->run + 1;
+ else
+ r->save -= 3;
+ }
+ else
+ r->run2++;
+ } else if (r->run2 > 0) {
+ if (r->run2 > 2)
+ r->save += r->run2;
+ else
+ r->save -= 3;
+ r->run2 = 0;
+ }
+
+ return v;
+}
+
+/* LOCO main predictor - LOCO-I/JPEG-LS predictor */
+static inline int loco_predict(uint8_t* data, int stride, int step)
+{
+ int max_ab, min_ab;
+ int a, b, c;
+
+ a = data[-stride];
+ b = data[-step];
+ c = data[-stride - step];
+
+ max_ab = (a > b) ? a : b;
+ min_ab = (a < b) ? a : b;
+
+ if (c >= max_ab) return min_ab;
+ if (c <= min_ab) return max_ab;
+ return (a + b - c);
+}
+
+static int loco_decode_plane(LOCOContext *l, uint8_t *data, int width, int height,
+ int stride, uint8_t *buf, int buf_size, int step)
+{
+ RICEContext rc;
+ int val;
+ int i, j;
+
+ init_get_bits(&rc.gb, buf, buf_size*8);
+ rc.save = 0;
+ rc.run = 0;
+ rc.run2 = 0;
+
+ rc.sum = 8;
+ rc.count = 1;
+
+ /* restore top left pixel */
+ val = loco_get_rice(&rc);
+ loco_update_rice_param(&rc, val);
+ if (val < 0) val -= l->lossy;
+ if (val > 0) val += l->lossy;
+ data[0] = 128 + val;
+ /* restore top line */
+ for (i = 1; i < width; i++) {
+ val = loco_get_rice(&rc);
+ loco_update_rice_param(&rc, val);
+ if (val < 0) val -= l->lossy;
+ if (val > 0) val += l->lossy;
+ data[i * step] = data[i * step - step] + val;
+ }
+ data += stride;
+ for (j = 1; j < height; j++) {
+ /* restore left column */
+ val = loco_get_rice(&rc);
+ loco_update_rice_param(&rc, val);
+ if (val < 0) val -= l->lossy;
+ if (val > 0) val += l->lossy;
+ data[0] = data[-stride] + val;
+ /* restore all other pixels */
+ for (i = 1; i < width; i++) {
+ val = loco_get_rice(&rc);
+ loco_update_rice_param(&rc, val);
+ if (val < 0) val -= l->lossy;
+ if (val > 0) val += l->lossy;
+ data[i * step] = loco_predict(&data[i * step], stride, step) + val;
+ }
+ data += stride;
+ }
+
+ return ((get_bits_count(&rc.gb) + 7) >> 3);
+}
+
+static int decode_frame(AVCodecContext *avctx,
+ void *data, int *data_size,
+ uint8_t *buf, int buf_size)
+{
+ LOCOContext * const l = avctx->priv_data;
+ AVFrame * const p= (AVFrame*)&l->pic;
+ int decoded;
+
+ if(p->data[0])
+ avctx->release_buffer(avctx, p);
+
+ p->reference = 0;
+ if(avctx->get_buffer(avctx, p) < 0){
+ av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
+ return -1;
+ }
+ p->key_frame = 1;
+
+ switch(l->mode) {
+ case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
+ decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 1);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height,
+ p->linesize[1], buf, buf_size, 1);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height,
+ p->linesize[2], buf, buf_size, 1);
+ break;
+ case LOCO_CYV12: case LOCO_YV12:
+ decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 1);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[1], avctx->width / 2, avctx->height / 2,
+ p->linesize[1], buf, buf_size, 1);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[2], avctx->width / 2, avctx->height / 2,
+ p->linesize[2], buf, buf_size, 1);
+ break;
+ case LOCO_CRGB: case LOCO_RGB:
+ decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 3);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[0] + 1, avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 3);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[0] + 2, avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 3);
+ break;
+ case LOCO_RGBA:
+ decoded = loco_decode_plane(l, p->data[0], avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 4);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[0] + 1, avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 4);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[0] + 2, avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 4);
+ buf += decoded; buf_size -= decoded;
+ decoded = loco_decode_plane(l, p->data[0] + 3, avctx->width, avctx->height,
+ p->linesize[0], buf, buf_size, 4);
+ break;
+ }
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame*)data = l->pic;
+
+ return buf_size;
+}
+
+static int decode_init(AVCodecContext *avctx){
+ LOCOContext * const l = avctx->priv_data;
+ int version;
+
+ l->avctx = avctx;
+ if (avctx->extradata_size < 12) {
+ av_log(avctx, AV_LOG_ERROR, "Extradata size must be >= 12 instead of %i\n",
+ avctx->extradata_size);
+ return -1;
+ }
+ version = LE_32(avctx->extradata);
+ switch(version) {
+ case 1:
+ l->lossy = 0;
+ break;
+ case 2:
+ l->lossy = LE_32(avctx->extradata + 8);
+ break;
+ default:
+ l->lossy = LE_32(avctx->extradata + 8);
+ av_log(avctx, AV_LOG_INFO, "This is LOCO codec version %i, please upload file for study\n", version);
+ }
+
+ l->mode = LE_32(avctx->extradata + 4);
+ switch(l->mode) {
+ case LOCO_CYUY2: case LOCO_YUY2: case LOCO_UYVY:
+ avctx->pix_fmt = PIX_FMT_YUV422P;
+ break;
+ case LOCO_CRGB: case LOCO_RGB:
+ avctx->pix_fmt = PIX_FMT_BGR24;
+ break;
+ case LOCO_CYV12: case LOCO_YV12:
+ avctx->pix_fmt = PIX_FMT_YUV420P;
+ break;
+ case LOCO_RGBA:
+ avctx->pix_fmt = PIX_FMT_RGBA32;
+ break;
+ default:
+ av_log(avctx, AV_LOG_INFO, "Unknown colorspace, index = %i\n", l->mode);
+ return -1;
+ }
+
+ return 0;
+}
+
+AVCodec loco_decoder = {
+ "loco",
+ CODEC_TYPE_VIDEO,
+ CODEC_ID_LOCO,
+ sizeof(LOCOContext),
+ decode_init,
+ NULL,
+ NULL,
+ decode_frame,
+ CODEC_CAP_DR1,
+};
projects / frescor / ffmpeg.git / commitdiff