--- /dev/null
+/*
+ * ZeroCodec Decoder
+ *
+ * Copyright (c) 2012, Derek Buitenhuis
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <zlib.h>
+
+#include "avcodec.h"
+
+typedef struct {
+ AVFrame previous_frame;
+ z_stream zstream;
+ int size;
+} ZeroCodecContext;
+
+static int zerocodec_decode_frame(AVCodecContext *avctx, void *data,
+ int *data_size, AVPacket *avpkt)
+{
+ ZeroCodecContext *zc = avctx->priv_data;
+ AVFrame *pic = avctx->coded_frame;
+ AVFrame *prev_pic = &zc->previous_frame;
+ z_stream *zstream = &zc->zstream;
+ uint8_t *prev, *dst;
+ int i, j, zret;
+
+ pic->reference = 3;
+
+ if (avctx->get_buffer(avctx, pic) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
+ return AVERROR(ENOMEM);
+ }
+
+ zret = inflateReset(zstream);
+
+ if (zret != Z_OK) {
+ av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d\n", zret);
+ return AVERROR(EINVAL);
+ }
+
+ zstream->next_in = avpkt->data;
+ zstream->avail_in = avpkt->size;
+
+ prev = prev_pic->data[0];
+ dst = pic->data[0];
+
+ /**
+ * ZeroCodec has very simple interframe compression. If a value
+ * is the same as the previous frame, set it to 0.
+ */
+
+ if (avpkt->flags & AV_PKT_FLAG_KEY) {
+
+ pic->key_frame = 1;
+ pic->pict_type = AV_PICTURE_TYPE_I;
+
+ for (i = 0; i < avctx->height; i++) {
+
+ zstream->next_out = dst;
+ zstream->avail_out = avctx->width << 1;
+
+ zret = inflate(zstream, Z_SYNC_FLUSH);
+
+ if (zret != Z_OK && zret != Z_STREAM_END) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Inflate failed with return code: %d\n", zret);
+ return AVERROR(EINVAL);
+ }
+
+ dst += pic->linesize[0];
+ }
+ } else {
+
+ pic->key_frame = 0;
+ pic->pict_type = AV_PICTURE_TYPE_P;
+
+ for (i = 0; i < avctx->height; i++) {
+
+ zstream->next_out = dst;
+ zstream->avail_out = avctx->width << 1;
+
+ zret = inflate(zstream, Z_SYNC_FLUSH);
+
+ if (zret != Z_OK && zret != Z_STREAM_END) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Inflate failed with return code: %d\n", zret);
+ return AVERROR(EINVAL);
+ }
+
+ for (j = 0; j < avctx->width << 1; j++)
+ dst[j] += prev[j] & -!dst[j];
+
+ prev += prev_pic->linesize[0];
+ dst += pic->linesize[0];
+ }
+ }
+
+ /* Release the previous buffer if need be */
+ if (prev_pic->data[0])
+ avctx->release_buffer(avctx, prev_pic);
+
+ /* Store the previouse frame for use later */
+ *prev_pic = *pic;
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame *)data = *pic;
+
+ return avpkt->size;
+}
+
+static av_cold int zerocodec_decode_close(AVCodecContext *avctx)
+{
+ ZeroCodecContext *zc = avctx->priv_data;
+ AVFrame *prev_pic = &zc->previous_frame;
+
+ inflateEnd(&zc->zstream);
+
+ /* Release last frame */
+ if (prev_pic->data[0])
+ avctx->release_buffer(avctx, prev_pic);
+
+ av_freep(&avctx->coded_frame);
+
+ return 0;
+}
+
+static av_cold int zerocodec_decode_init(AVCodecContext *avctx)
+{
+ ZeroCodecContext *zc = avctx->priv_data;
+ z_stream *zstream = &zc->zstream;
+ int zret;
+
+ avctx->pix_fmt = PIX_FMT_UYVY422;
+ avctx->bits_per_raw_sample = 8;
+
+ zc->size = avpicture_get_size(avctx->pix_fmt,
+ avctx->width, avctx->height);
+
+ zstream->zalloc = Z_NULL;
+ zstream->zfree = Z_NULL;
+ zstream->opaque = Z_NULL;
+
+ zret = inflateInit(zstream);
+
+ if (zret != Z_OK) {
+ av_log(avctx, AV_LOG_ERROR, "Could not initialize inflate: %d\n", zret);
+ return AVERROR(ENOMEM);
+ }
+
+ avctx->coded_frame = avcodec_alloc_frame();
+
+ if (!avctx->coded_frame) {
+ av_log(avctx, AV_LOG_ERROR, "Could not allocate frame buffer.\n");
+ zerocodec_decode_close(avctx);
+ return AVERROR(ENOMEM);
+ }
+
+ return 0;
+}
+
+AVCodec ff_zerocodec_decoder = {
+ .type = AVMEDIA_TYPE_VIDEO,
+ .name = "zerocodec",
+ .id = CODEC_ID_ZEROCODEC,
+ .priv_data_size = sizeof(ZeroCodecContext),
+ .init = zerocodec_decode_init,
+ .decode = zerocodec_decode_frame,
+ .close = zerocodec_decode_close,
+ .capabilities = CODEC_CAP_DR1,
+ .long_name = NULL_IF_CONFIG_SMALL("ZeroCodec Lossless Video"),
+};