/* * 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" #include "internal.h" #include "libavutil/common.h" typedef struct { AVFrame previous_frame; z_stream zstream; } ZeroCodecContext; static int zerocodec_decode_frame(AVCodecContext *avctx, void *data, int *got_frame, 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 = prev_pic->data[0]; uint8_t *dst; int i, j, zret; pic->reference = 3; if (avpkt->flags & AV_PKT_FLAG_KEY) { pic->key_frame = 1; pic->pict_type = AV_PICTURE_TYPE_I; } else { if (!prev) { av_log(avctx, AV_LOG_ERROR, "Missing reference frame.\n"); return AVERROR_INVALIDDATA; } prev += (avctx->height - 1) * prev_pic->linesize[0]; pic->key_frame = 0; pic->pict_type = AV_PICTURE_TYPE_P; } zret = inflateReset(zstream); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret); return AVERROR_INVALIDDATA; } if (ff_get_buffer(avctx, pic) < 0) { av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n"); return AVERROR(ENOMEM); } zstream->next_in = avpkt->data; zstream->avail_in = avpkt->size; dst = pic->data[0] + (avctx->height - 1) * pic->linesize[0]; /** * ZeroCodec has very simple interframe compression. If a value * is the same as the previous frame, set it to 0. */ 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) { avctx->release_buffer(avctx, pic); av_log(avctx, AV_LOG_ERROR, "Inflate failed with return code: %d.\n", zret); return AVERROR_INVALIDDATA; } if (!(avpkt->flags & AV_PKT_FLAG_KEY)) 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); *got_frame = 1; *(AVFrame *)data = *pic; /* Store the previous frame for use later. * FFSWAP ensures that e.g. pic->data is NULLed. */ FFSWAP(AVFrame, *pic, *prev_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 = AV_PIX_FMT_UYVY422; avctx->bits_per_raw_sample = 8; 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 = AV_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"), };