lavc: split LSCR decoder out of PNG decoder

It shares very little code with pngdec, so keeping them together only
makes the code harder to read.

1 files changed, 6 insertions, 168 deletions

diff --git a/libavcodec/pngdec.c b/libavcodec/pngdec.c
index 61642b7cbe..e05e44f564 100644
--- a/libavcodec/pngdec.c
+++ b/libavcodec/pngdec.c
@@ -250,8 +250,8 @@ void ff_add_png_paeth_prediction(uint8_t *dst, uint8_t *src, uint8_t *top,
     }
 
 /* NOTE: 'dst' can be equal to 'last' */
-static void png_filter_row(PNGDSPContext *dsp, uint8_t *dst, int filter_type,
-                           uint8_t *src, uint8_t *last, int size, int bpp)
+void ff_png_filter_row(PNGDSPContext *dsp, uint8_t *dst, int filter_type,
+                       uint8_t *src, uint8_t *last, int size, int bpp)
 {
     int i, p, r, g, b, a;
 
@@ -343,8 +343,8 @@ static void png_handle_row(PNGDecContext *s)
         else
             last_row = ptr - s->image_linesize;
 
-        png_filter_row(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1,
-                       last_row, s->row_size, s->bpp);
+        ff_png_filter_row(&s->dsp, ptr, s->crow_buf[0], s->crow_buf + 1,
+                          last_row, s->row_size, s->bpp);
         /* loco lags by 1 row so that it doesn't interfere with top prediction */
         if (s->filter_type == PNG_FILTER_TYPE_LOCO && s->y > 0) {
             if (s->bit_depth == 16) {
@@ -377,8 +377,8 @@ static void png_handle_row(PNGDecContext *s)
                  * wait for the next one */
                 if (got_line)
                     break;
-                png_filter_row(&s->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
-                               s->last_row, s->pass_row_size, s->bpp);
+                ff_png_filter_row(&s->dsp, s->tmp_row, s->crow_buf[0], s->crow_buf + 1,
+                                  s->last_row, s->pass_row_size, s->bpp);
                 FFSWAP(uint8_t *, s->last_row, s->tmp_row);
                 FFSWAP(unsigned int, s->last_row_size, s->tmp_row_size);
                 got_line = 1;
@@ -1585,148 +1585,6 @@ end:
 }
 #endif
 
-#if CONFIG_LSCR_DECODER
-static int decode_frame_lscr(AVCodecContext *avctx,
-                             void *data, int *got_frame,
-                             AVPacket *avpkt)
-{
-    PNGDecContext *const s = avctx->priv_data;
-    GetByteContext *gb = &s->gb;
-    AVFrame *frame = data;
-    int ret, nb_blocks, offset = 0;
-
-    if (avpkt->size < 2)
-        return AVERROR_INVALIDDATA;
-    if (avpkt->size == 2)
-        return 0;
-
-    bytestream2_init(gb, avpkt->data, avpkt->size);
-
-    if ((ret = ff_get_buffer(avctx, frame, AV_GET_BUFFER_FLAG_REF)) < 0)
-        return ret;
-
-    nb_blocks = bytestream2_get_le16(gb);
-    if (bytestream2_get_bytes_left(gb) < 2 + nb_blocks * (12 + 8))
-        return AVERROR_INVALIDDATA;
-
-    if (s->last_picture.f->data[0]) {
-        ret = av_frame_copy(frame, s->last_picture.f);
-        if (ret < 0)
-            return ret;
-    }
-
-    for (int b = 0; b < nb_blocks; b++) {
-        int x, y, x2, y2, w, h, left;
-        uint32_t csize, size;
-
-        s->zstream.zalloc = ff_png_zalloc;
-        s->zstream.zfree  = ff_png_zfree;
-        s->zstream.opaque = NULL;
-
-        if ((ret = inflateInit(&s->zstream)) != Z_OK) {
-            av_log(avctx, AV_LOG_ERROR, "inflateInit returned error %d\n", ret);
-            ret = AVERROR_EXTERNAL;
-            goto end;
-        }
-
-        bytestream2_seek(gb, 2 + b * 12, SEEK_SET);
-
-        x = bytestream2_get_le16(gb);
-        y = bytestream2_get_le16(gb);
-        x2 = bytestream2_get_le16(gb);
-        y2 = bytestream2_get_le16(gb);
-        s->width  = s->cur_w = w = x2-x;
-        s->height = s->cur_h = h = y2-y;
-
-        if (w <= 0 || x < 0 || x >= avctx->width || w + x > avctx->width ||
-            h <= 0 || y < 0 || y >= avctx->height || h + y > avctx->height) {
-            ret = AVERROR_INVALIDDATA;
-            goto end;
-        }
-
-        size = bytestream2_get_le32(gb);
-
-        frame->key_frame = (nb_blocks == 1) &&
-                           (w == avctx->width) &&
-                           (h == avctx->height) &&
-                           (x == 0) && (y == 0);
-
-        bytestream2_seek(gb, 2 + nb_blocks * 12 + offset, SEEK_SET);
-        csize = bytestream2_get_be32(gb);
-        if (bytestream2_get_le32(gb) != MKTAG('I', 'D', 'A', 'T')) {
-            ret = AVERROR_INVALIDDATA;
-            goto end;
-        }
-
-        offset += size;
-        left = size;
-
-        s->y                 = 0;
-        s->row_size          = w * 3;
-
-        av_fast_padded_malloc(&s->buffer, &s->buffer_size, s->row_size + 16);
-        if (!s->buffer) {
-            ret = AVERROR(ENOMEM);
-            goto end;
-        }
-
-        av_fast_padded_malloc(&s->last_row, &s->last_row_size, s->row_size);
-        if (!s->last_row) {
-            ret = AVERROR(ENOMEM);
-            goto end;
-        }
-
-        s->crow_size         = w * 3 + 1;
-        s->crow_buf          = s->buffer + 15;
-        s->zstream.avail_out = s->crow_size;
-        s->zstream.next_out  = s->crow_buf;
-        s->image_buf         = frame->data[0] + (avctx->height - y - 1) * frame->linesize[0] + x * 3;
-        s->image_linesize    =-frame->linesize[0];
-        s->bpp               = 3;
-        s->pic_state         = 0;
-
-        while (left > 16) {
-            ret = png_decode_idat(s, csize);
-            if (ret < 0)
-                goto end;
-            left -= csize + 16;
-            if (left > 16) {
-                bytestream2_skip(gb, 4);
-                csize = bytestream2_get_be32(gb);
-                if (bytestream2_get_le32(gb) != MKTAG('I', 'D', 'A', 'T')) {
-                    ret = AVERROR_INVALIDDATA;
-                    goto end;
-                }
-            }
-        }
-
-        inflateEnd(&s->zstream);
-    }
-
-    frame->pict_type = frame->key_frame ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
-
-    av_frame_unref(s->last_picture.f);
-    if ((ret = av_frame_ref(s->last_picture.f, frame)) < 0)
-        return ret;
-
-    *got_frame = 1;
-end:
-    inflateEnd(&s->zstream);
-
-    if (ret < 0)
-        return ret;
-    return avpkt->size;
-}
-
-static void decode_flush(AVCodecContext *avctx)
-{
-    PNGDecContext *s = avctx->priv_data;
-
-    av_frame_unref(s->last_picture.f);
-}
-
-#endif
-
 #if HAVE_THREADS
 static int update_thread_context(AVCodecContext *dst, const AVCodecContext *src)
 {
@@ -1783,9 +1641,6 @@ static av_cold int png_dec_init(AVCodecContext *avctx)
 
     avctx->color_range = AVCOL_RANGE_JPEG;
 
-    if (avctx->codec_id == AV_CODEC_ID_LSCR)
-        avctx->pix_fmt = AV_PIX_FMT_BGR24;
-
     s->avctx = avctx;
     s->previous_picture.f = av_frame_alloc();
     s->last_picture.f = av_frame_alloc();
@@ -1855,20 +1710,3 @@ AVCodec ff_png_decoder = {
                       FF_CODEC_CAP_ALLOCATE_PROGRESS,
 };
 #endif
-
-#if CONFIG_LSCR_DECODER
-AVCodec ff_lscr_decoder = {
-    .name           = "lscr",
-    .long_name      = NULL_IF_CONFIG_SMALL("LEAD Screen Capture"),
-    .type           = AVMEDIA_TYPE_VIDEO,
-    .id             = AV_CODEC_ID_LSCR,
-    .priv_data_size = sizeof(PNGDecContext),
-    .init           = png_dec_init,
-    .close          = png_dec_end,
-    .decode         = decode_frame_lscr,
-    .flush          = decode_flush,
-    .capabilities   = AV_CODEC_CAP_DR1 /*| AV_CODEC_CAP_DRAW_HORIZ_BAND*/,
-    .caps_internal  = FF_CODEC_CAP_SKIP_FRAME_FILL_PARAM | FF_CODEC_CAP_INIT_THREADSAFE |
-                      FF_CODEC_CAP_ALLOCATE_PROGRESS,
-};
-#endif