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diff --git a/ffmpeg/libavcodec/flashsvenc.c b/ffmpeg/libavcodec/flashsvenc.c
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+/*
+ * Flash Screen Video encoder
+ * Copyright (C) 2004 Alex Beregszaszi
+ * Copyright (C) 2006 Benjamin Larsson
+ *
+ * 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
+ */
+
+/* Encoding development sponsored by http://fh-campuswien.ac.at */
+
+/**
+ * @file
+ * Flash Screen Video encoder
+ * @author Alex Beregszaszi
+ * @author Benjamin Larsson
+ *
+ * A description of the bitstream format for Flash Screen Video version 1/2
+ * is part of the SWF File Format Specification (version 10), which can be
+ * downloaded from http://www.adobe.com/devnet/swf.html.
+ */
+
+/*
+ * Encoding ideas: A basic encoder would just use a fixed block size.
+ * Block sizes can be multiples of 16, from 16 to 256. The blocks don't
+ * have to be quadratic. A brute force search with a set of different
+ * block sizes should give a better result than to just use a fixed size.
+ *
+ * TODO:
+ * Don't reencode the frame in brute force mode if the frame is a dupe.
+ * Speed up. Make the difference check faster.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <zlib.h>
+
+#include "avcodec.h"
+#include "internal.h"
+#include "put_bits.h"
+#include "bytestream.h"
+
+
+typedef struct FlashSVContext {
+ AVCodecContext *avctx;
+ uint8_t *previous_frame;
+ AVFrame frame;
+ int image_width, image_height;
+ int block_width, block_height;
+ uint8_t *tmpblock;
+ uint8_t *encbuffer;
+ int block_size;
+ z_stream zstream;
+ int last_key_frame;
+} FlashSVContext;
+
+static int copy_region_enc(uint8_t *sptr, uint8_t *dptr, int dx, int dy,
+ int h, int w, int stride, uint8_t *pfptr)
+{
+ int i, j;
+ uint8_t *nsptr;
+ uint8_t *npfptr;
+ int diff = 0;
+
+ for (i = dx + h; i > dx; i--) {
+ nsptr = sptr + i * stride + dy * 3;
+ npfptr = pfptr + i * stride + dy * 3;
+ for (j = 0; j < w * 3; j++) {
+ diff |= npfptr[j] ^ nsptr[j];
+ dptr[j] = nsptr[j];
+ }
+ dptr += w * 3;
+ }
+ if (diff)
+ return 1;
+ return 0;
+}
+
+static av_cold int flashsv_encode_init(AVCodecContext *avctx)
+{
+ FlashSVContext *s = avctx->priv_data;
+
+ s->avctx = avctx;
+
+ if (avctx->width > 4095 || avctx->height > 4095) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Input dimensions too large, input must be max 4096x4096 !\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ // Needed if zlib unused or init aborted before deflateInit
+ memset(&s->zstream, 0, sizeof(z_stream));
+
+ s->last_key_frame = 0;
+
+ s->image_width = avctx->width;
+ s->image_height = avctx->height;
+
+ s->tmpblock = av_mallocz(3 * 256 * 256);
+ s->encbuffer = av_mallocz(s->image_width * s->image_height * 3);
+
+ if (!s->tmpblock || !s->encbuffer) {
+ av_log(avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
+ return AVERROR(ENOMEM);
+ }
+
+ return 0;
+}
+
+
+static int encode_bitstream(FlashSVContext *s, AVFrame *p, uint8_t *buf,
+ int buf_size, int block_width, int block_height,
+ uint8_t *previous_frame, int *I_frame)
+{
+
+ PutBitContext pb;
+ int h_blocks, v_blocks, h_part, v_part, i, j;
+ int buf_pos, res;
+ int pred_blocks = 0;
+
+ init_put_bits(&pb, buf, buf_size * 8);
+
+ put_bits(&pb, 4, block_width / 16 - 1);
+ put_bits(&pb, 12, s->image_width);
+ put_bits(&pb, 4, block_height / 16 - 1);
+ put_bits(&pb, 12, s->image_height);
+ flush_put_bits(&pb);
+ buf_pos = 4;
+
+ h_blocks = s->image_width / block_width;
+ h_part = s->image_width % block_width;
+ v_blocks = s->image_height / block_height;
+ v_part = s->image_height % block_height;
+
+ /* loop over all block columns */
+ for (j = 0; j < v_blocks + (v_part ? 1 : 0); j++) {
+
+ int y_pos = j * block_height; // vertical position in frame
+ int cur_blk_height = (j < v_blocks) ? block_height : v_part;
+
+ /* loop over all block rows */
+ for (i = 0; i < h_blocks + (h_part ? 1 : 0); i++) {
+ int x_pos = i * block_width; // horizontal position in frame
+ int cur_blk_width = (i < h_blocks) ? block_width : h_part;
+ int ret = Z_OK;
+ uint8_t *ptr = buf + buf_pos;
+
+ /* copy the block to the temp buffer before compression
+ * (if it differs from the previous frame's block) */
+ res = copy_region_enc(p->data[0], s->tmpblock,
+ s->image_height - (y_pos + cur_blk_height + 1),
+ x_pos, cur_blk_height, cur_blk_width,
+ p->linesize[0], previous_frame);
+
+ if (res || *I_frame) {
+ unsigned long zsize = 3 * block_width * block_height;
+ ret = compress2(ptr + 2, &zsize, s->tmpblock,
+ 3 * cur_blk_width * cur_blk_height, 9);
+
+ //ret = deflateReset(&s->zstream);
+ if (ret != Z_OK)
+ av_log(s->avctx, AV_LOG_ERROR,
+ "error while compressing block %dx%d\n", i, j);
+
+ bytestream_put_be16(&ptr, zsize);
+ buf_pos += zsize + 2;
+ av_dlog(s->avctx, "buf_pos = %d\n", buf_pos);
+ } else {
+ pred_blocks++;
+ bytestream_put_be16(&ptr, 0);
+ buf_pos += 2;
+ }
+ }
+ }
+
+ if (pred_blocks)
+ *I_frame = 0;
+ else
+ *I_frame = 1;
+
+ return buf_pos;
+}
+
+
+static int flashsv_encode_frame(AVCodecContext *avctx, AVPacket *pkt,
+ const AVFrame *pict, int *got_packet)
+{
+ FlashSVContext * const s = avctx->priv_data;
+ AVFrame * const p = &s->frame;
+ uint8_t *pfptr;
+ int res;
+ int I_frame = 0;
+ int opt_w = 4, opt_h = 4;
+
+ *p = *pict;
+
+ /* First frame needs to be a keyframe */
+ if (avctx->frame_number == 0) {
+ s->previous_frame = av_mallocz(FFABS(p->linesize[0]) * s->image_height);
+ if (!s->previous_frame) {
+ av_log(avctx, AV_LOG_ERROR, "Memory allocation failed.\n");
+ return AVERROR(ENOMEM);
+ }
+ I_frame = 1;
+ }
+
+ if (p->linesize[0] < 0)
+ pfptr = s->previous_frame - (s->image_height - 1) * p->linesize[0];
+ else
+ pfptr = s->previous_frame;
+
+ /* Check the placement of keyframes */
+ if (avctx->gop_size > 0 &&
+ avctx->frame_number >= s->last_key_frame + avctx->gop_size) {
+ I_frame = 1;
+ }
+
+ if ((res = ff_alloc_packet2(avctx, pkt, s->image_width * s->image_height * 3)) < 0)
+ return res;
+
+ pkt->size = encode_bitstream(s, p, pkt->data, pkt->size, opt_w * 16, opt_h * 16,
+ pfptr, &I_frame);
+
+ //save the current frame
+ if (p->linesize[0] > 0)
+ memcpy(s->previous_frame, p->data[0], s->image_height * p->linesize[0]);
+ else
+ memcpy(s->previous_frame,
+ p->data[0] + p->linesize[0] * (s->image_height - 1),
+ s->image_height * FFABS(p->linesize[0]));
+
+ //mark the frame type so the muxer can mux it correctly
+ if (I_frame) {
+ p->pict_type = AV_PICTURE_TYPE_I;
+ p->key_frame = 1;
+ s->last_key_frame = avctx->frame_number;
+ av_dlog(avctx, "Inserting keyframe at frame %d\n", avctx->frame_number);
+ } else {
+ p->pict_type = AV_PICTURE_TYPE_P;
+ p->key_frame = 0;
+ }
+
+ avctx->coded_frame = p;
+
+ if (p->key_frame)
+ pkt->flags |= AV_PKT_FLAG_KEY;
+ *got_packet = 1;
+
+ return 0;
+}
+
+static av_cold int flashsv_encode_end(AVCodecContext *avctx)
+{
+ FlashSVContext *s = avctx->priv_data;
+
+ deflateEnd(&s->zstream);
+
+ av_free(s->encbuffer);
+ av_free(s->previous_frame);
+ av_free(s->tmpblock);
+
+ return 0;
+}
+
+AVCodec ff_flashsv_encoder = {
+ .name = "flashsv",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_FLASHSV,
+ .priv_data_size = sizeof(FlashSVContext),
+ .init = flashsv_encode_init,
+ .encode2 = flashsv_encode_frame,
+ .close = flashsv_encode_end,
+ .pix_fmts = (const enum AVPixelFormat[]){ AV_PIX_FMT_BGR24, AV_PIX_FMT_NONE },
+ .long_name = NULL_IF_CONFIG_SMALL("Flash Screen Video"),
+};
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