/* * PDV video format * * Copyright (c) 2023 Paul B Mahol * * 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 */ #include "avcodec.h" #include "codec_internal.h" #include "decode.h" #include "zlib_wrapper.h" #include <zlib.h> typedef struct PDVContext { AVFrame *previous_frame; FFZStream zstream; } PDVContext; static av_cold int decode_init(AVCodecContext *avctx) { PDVContext *s = avctx->priv_data; avctx->pix_fmt = AV_PIX_FMT_MONOBLACK; s->previous_frame = av_frame_alloc(); if (!s->previous_frame) return AVERROR(ENOMEM); return ff_inflate_init(&s->zstream, avctx); } static av_cold int decode_end(AVCodecContext *avctx) { PDVContext *s = avctx->priv_data; av_frame_free(&s->previous_frame); ff_inflate_end(&s->zstream); return 0; } static int decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame, AVPacket *avpkt) { PDVContext *s = avctx->priv_data; AVFrame *prev_frame = s->previous_frame; z_stream *const zstream = &s->zstream.zstream; uint8_t *dst, *prev = prev_frame->data[0]; int ret, zret; if (avctx->skip_frame >= AVDISCARD_ALL || (avctx->skip_frame >= AVDISCARD_NONINTRA && !(avpkt->flags & AV_PKT_FLAG_KEY))) return avpkt->size; zret = inflateReset(zstream); if (zret != Z_OK) { av_log(avctx, AV_LOG_ERROR, "Could not reset inflate: %d.\n", zret); return AVERROR_INVALIDDATA; } if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0) return ret; zstream->next_in = avpkt->data; zstream->avail_in = avpkt->size; dst = frame->data[0]; for (int i = 0; i < avctx->height; i++) { zstream->next_out = dst; zstream->avail_out = (avctx->width + 7) >> 3; 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_INVALIDDATA; } if (prev && !(avpkt->flags & AV_PKT_FLAG_KEY)) { for (int j = 0; j < (avctx->width + 7) >> 3; j++) dst[j] ^= prev[j]; prev += prev_frame->linesize[0]; } dst += frame->linesize[0]; } if ((ret = av_frame_replace(s->previous_frame, frame)) < 0) return ret; if (avpkt->flags & AV_PKT_FLAG_KEY) { frame->flags |= AV_FRAME_FLAG_KEY; frame->pict_type = AV_PICTURE_TYPE_I; } else { frame->pict_type = AV_PICTURE_TYPE_P; } *got_frame = 1; return avpkt->size; } static void decode_flush(AVCodecContext *avctx) { PDVContext *s = avctx->priv_data; av_frame_unref(s->previous_frame); } const FFCodec ff_pdv_decoder = { .p.name = "pdv", CODEC_LONG_NAME("PDV (PlayDate Video)"), .priv_data_size = sizeof(PDVContext), .p.type = AVMEDIA_TYPE_VIDEO, .p.id = AV_CODEC_ID_PDV, .p.capabilities = AV_CODEC_CAP_DR1, .caps_internal = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM | FF_CODEC_CAP_INIT_CLEANUP, .init = decode_init, .close = decode_end, .flush = decode_flush, FF_CODEC_DECODE_CB(decode_frame), };