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Diffstat (limited to 'src/libffmpeg/libavcodec/idcinvideo.c')
-rw-r--r--src/libffmpeg/libavcodec/idcinvideo.c272
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diff --git a/src/libffmpeg/libavcodec/idcinvideo.c b/src/libffmpeg/libavcodec/idcinvideo.c
deleted file mode 100644
index 112da7bc6..000000000
--- a/src/libffmpeg/libavcodec/idcinvideo.c
+++ /dev/null
@@ -1,272 +0,0 @@
-/*
- * Id Quake II CIN Video Decoder
- * Copyright (C) 2003 the ffmpeg project
- *
- * 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 idcinvideo.c
- * Id Quake II Cin Video Decoder by Dr. Tim Ferguson
- * For more information about the Id CIN format, visit:
- * http://www.csse.monash.edu.au/~timf/
- *
- * This video decoder outputs PAL8 colorspace data. Interacting with this
- * decoder is a little involved. During initialization, the demuxer must
- * transmit the 65536-byte Huffman table(s) to the decoder via extradata.
- * Then, whenever a palette change is encountered while demuxing the file,
- * the demuxer must use the same extradata space to transmit an
- * AVPaletteControl structure.
- *
- * Id CIN video is purely Huffman-coded, intraframe-only codec. It achieves
- * a little more compression by exploiting the fact that adjacent pixels
- * tend to be similar.
- *
- * Note that this decoder could use ffmpeg's optimized VLC facilities
- * rather than naive, tree-based Huffman decoding. However, there are 256
- * Huffman tables. Plus, the VLC bit coding order is right -> left instead
- * or left -> right, so all of the bits would have to be reversed. Further,
- * the original Quake II implementation likely used a similar naive
- * decoding algorithm and it worked fine on much lower spec machines.
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include "common.h"
-#include "avcodec.h"
-#include "dsputil.h"
-
-#define HUFFMAN_TABLE_SIZE 64 * 1024
-#define HUF_TOKENS 256
-#define PALETTE_COUNT 256
-
-typedef struct
-{
- int count;
- unsigned char used;
- int children[2];
-} hnode_t;
-
-typedef struct IdcinContext {
-
- AVCodecContext *avctx;
- DSPContext dsp;
- AVFrame frame;
-
- unsigned char *buf;
- int size;
-
- hnode_t huff_nodes[256][HUF_TOKENS*2];
- int num_huff_nodes[256];
-
-} IdcinContext;
-
-/*
- * Find the lowest probability node in a Huffman table, and mark it as
- * being assigned to a higher probability.
- * Returns the node index of the lowest unused node, or -1 if all nodes
- * are used.
- */
-static int huff_smallest_node(hnode_t *hnodes, int num_hnodes) {
- int i;
- int best, best_node;
-
- best = 99999999;
- best_node = -1;
- for(i = 0; i < num_hnodes; i++) {
- if(hnodes[i].used)
- continue;
- if(!hnodes[i].count)
- continue;
- if(hnodes[i].count < best) {
- best = hnodes[i].count;
- best_node = i;
- }
- }
-
- if(best_node == -1)
- return -1;
- hnodes[best_node].used = 1;
- return best_node;
-}
-
-/*
- * Build the Huffman tree using the generated/loaded probabilities histogram.
- *
- * On completion:
- * huff_nodes[prev][i < HUF_TOKENS] - are the nodes at the base of the tree.
- * huff_nodes[prev][i >= HUF_TOKENS] - are used to construct the tree.
- * num_huff_nodes[prev] - contains the index to the root node of the tree.
- * That is: huff_nodes[prev][num_huff_nodes[prev]] is the root node.
- */
-static void huff_build_tree(IdcinContext *s, int prev) {
- hnode_t *node, *hnodes;
- int num_hnodes, i;
-
- num_hnodes = HUF_TOKENS;
- hnodes = s->huff_nodes[prev];
- for(i = 0; i < HUF_TOKENS * 2; i++)
- hnodes[i].used = 0;
-
- while (1) {
- node = &hnodes[num_hnodes]; /* next free node */
-
- /* pick two lowest counts */
- node->children[0] = huff_smallest_node(hnodes, num_hnodes);
- if(node->children[0] == -1)
- break; /* reached the root node */
-
- node->children[1] = huff_smallest_node(hnodes, num_hnodes);
- if(node->children[1] == -1)
- break; /* reached the root node */
-
- /* combine nodes probability for new node */
- node->count = hnodes[node->children[0]].count +
- hnodes[node->children[1]].count;
- num_hnodes++;
- }
-
- s->num_huff_nodes[prev] = num_hnodes - 1;
-}
-
-static int idcin_decode_init(AVCodecContext *avctx)
-{
- IdcinContext *s = (IdcinContext *)avctx->priv_data;
- int i, j, histogram_index = 0;
- unsigned char *histograms;
-
- s->avctx = avctx;
- avctx->pix_fmt = PIX_FMT_PAL8;
- avctx->has_b_frames = 0;
- dsputil_init(&s->dsp, avctx);
-
- /* make sure the Huffman tables make it */
- if (s->avctx->extradata_size != HUFFMAN_TABLE_SIZE) {
- av_log(s->avctx, AV_LOG_ERROR, " Id CIN video: expected extradata size of %d\n", HUFFMAN_TABLE_SIZE);
- return -1;
- }
-
- /* build the 256 Huffman decode trees */
- histograms = (unsigned char *)s->avctx->extradata;
- for (i = 0; i < 256; i++) {
- for(j = 0; j < HUF_TOKENS; j++)
- s->huff_nodes[i][j].count = histograms[histogram_index++];
- huff_build_tree(s, i);
- }
-
- s->frame.data[0] = NULL;
-
- return 0;
-}
-
-static void idcin_decode_vlcs(IdcinContext *s)
-{
- hnode_t *hnodes;
- long x, y;
- int prev;
- unsigned char v = 0;
- int bit_pos, node_num, dat_pos;
-
- prev = bit_pos = dat_pos = 0;
- for (y = 0; y < (s->frame.linesize[0] * s->avctx->height);
- y += s->frame.linesize[0]) {
- for (x = y; x < y + s->avctx->width; x++) {
- node_num = s->num_huff_nodes[prev];
- hnodes = s->huff_nodes[prev];
-
- while(node_num >= HUF_TOKENS) {
- if(!bit_pos) {
- if(dat_pos >= s->size) {
- av_log(s->avctx, AV_LOG_ERROR, "Huffman decode error.\n");
- return;
- }
- bit_pos = 8;
- v = s->buf[dat_pos++];
- }
-
- node_num = hnodes[node_num].children[v & 0x01];
- v = v >> 1;
- bit_pos--;
- }
-
- s->frame.data[0][x] = node_num;
- prev = node_num;
- }
- }
-}
-
-static int idcin_decode_frame(AVCodecContext *avctx,
- void *data, int *data_size,
- uint8_t *buf, int buf_size)
-{
- IdcinContext *s = (IdcinContext *)avctx->priv_data;
- AVPaletteControl *palette_control = avctx->palctrl;
-
- s->buf = buf;
- s->size = buf_size;
-
- if (s->frame.data[0])
- avctx->release_buffer(avctx, &s->frame);
-
- if (avctx->get_buffer(avctx, &s->frame)) {
- av_log(avctx, AV_LOG_ERROR, " Id CIN Video: get_buffer() failed\n");
- return -1;
- }
-
- idcin_decode_vlcs(s);
-
- /* make the palette available on the way out */
- memcpy(s->frame.data[1], palette_control->palette, PALETTE_COUNT * 4);
- /* If palette changed inform application*/
- if (palette_control->palette_changed) {
- palette_control->palette_changed = 0;
- s->frame.palette_has_changed = 1;
- }
-
- *data_size = sizeof(AVFrame);
- *(AVFrame*)data = s->frame;
-
- /* report that the buffer was completely consumed */
- return buf_size;
-}
-
-static int idcin_decode_end(AVCodecContext *avctx)
-{
- IdcinContext *s = (IdcinContext *)avctx->priv_data;
-
- if (s->frame.data[0])
- avctx->release_buffer(avctx, &s->frame);
-
- return 0;
-}
-
-AVCodec idcin_decoder = {
- "idcinvideo",
- CODEC_TYPE_VIDEO,
- CODEC_ID_IDCIN,
- sizeof(IdcinContext),
- idcin_decode_init,
- NULL,
- idcin_decode_end,
- idcin_decode_frame,
- CODEC_CAP_DR1,
-};
-
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-25 18:08:32 +0000