mpegvideo: Move Picture-related functions to a separate file

5 files changed, 536 insertions, 474 deletions

diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 629d25d..58f548a 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -77,7 +77,7 @@ OBJS-$(CONFIG_MPEGAUDIODSP)            += mpegaudiodsp.o                \
                                           mpegaudiodsp_float.o
 OBJS-$(CONFIG_MPEGVIDEO)               += mpegvideo.o mpegvideodsp.o rl.o \
                                           mpegvideo_motion.o mpegutils.o \
-                                          mpegvideodata.o
+                                          mpegvideodata.o mpegpicture.o
 OBJS-$(CONFIG_MPEGVIDEOENC)            += mpegvideo_enc.o mpeg12data.o  \
                                           motion_est.o ratecontrol.o    \
                                           mpegvideoencdsp.o
diff --git a/libavcodec/mpegpicture.c b/libavcodec/mpegpicture.c
new file mode 100644
index 0000000..9df1415
--- /dev/null
+++ b/libavcodec/mpegpicture.c
@@ -0,0 +1,424 @@
+/*
+ * Mpeg video formats-related picture management functions
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+
+#include "libavutil/avassert.h"
+#include "libavutil/common.h"
+
+#include "avcodec.h"
+#include "motion_est.h"
+#include "mpegpicture.h"
+#include "mpegutils.h"
+
+static int make_tables_writable(Picture *pic)
+{
+    int ret, i;
+#define MAKE_WRITABLE(table) \
+do {\
+    if (pic->table &&\
+       (ret = av_buffer_make_writable(&pic->table)) < 0)\
+    return ret;\
+} while (0)
+
+    MAKE_WRITABLE(mb_var_buf);
+    MAKE_WRITABLE(mc_mb_var_buf);
+    MAKE_WRITABLE(mb_mean_buf);
+    MAKE_WRITABLE(mbskip_table_buf);
+    MAKE_WRITABLE(qscale_table_buf);
+    MAKE_WRITABLE(mb_type_buf);
+
+    for (i = 0; i < 2; i++) {
+        MAKE_WRITABLE(motion_val_buf[i]);
+        MAKE_WRITABLE(ref_index_buf[i]);
+    }
+
+    return 0;
+}
+
+int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
+                            ScratchpadContext *sc, int linesize)
+{
+    int alloc_size = FFALIGN(FFABS(linesize) + 32, 32);
+
+    // edge emu needs blocksize + filter length - 1
+    // (= 17x17 for  halfpel / 21x21 for  h264)
+    // VC1 computes luma and chroma simultaneously and needs 19X19 + 9x9
+    // at uvlinesize. It supports only YUV420 so 24x24 is enough
+    // linesize * interlaced * MBsize
+    FF_ALLOCZ_OR_GOTO(avctx, sc->edge_emu_buffer, alloc_size * 2 * 24,
+                      fail);
+
+    FF_ALLOCZ_OR_GOTO(avctx, me->scratchpad, alloc_size * 2 * 16 * 3,
+                      fail)
+    me->temp            = me->scratchpad;
+    sc->rd_scratchpad   = me->scratchpad;
+    sc->b_scratchpad    = me->scratchpad;
+    sc->obmc_scratchpad = me->scratchpad + 16;
+
+    return 0;
+fail:
+    av_freep(&sc->edge_emu_buffer);
+    return AVERROR(ENOMEM);
+}
+
+/**
+ * Allocate a frame buffer
+ */
+static int alloc_frame_buffer(AVCodecContext *avctx,  Picture *pic,
+                              MotionEstContext *me, ScratchpadContext *sc,
+                              int chroma_x_shift, int chroma_y_shift,
+                              int linesize, int uvlinesize)
+{
+    int edges_needed = av_codec_is_encoder(avctx->codec);
+    int r, ret;
+
+    pic->tf.f = pic->f;
+    if (avctx->codec_id != AV_CODEC_ID_WMV3IMAGE &&
+        avctx->codec_id != AV_CODEC_ID_VC1IMAGE  &&
+        avctx->codec_id != AV_CODEC_ID_MSS2) {
+        if (edges_needed) {
+            pic->f->width  = avctx->width  + 2 * EDGE_WIDTH;
+            pic->f->height = avctx->height + 2 * EDGE_WIDTH;
+        }
+
+        r = ff_thread_get_buffer(avctx, &pic->tf,
+                                 pic->reference ? AV_GET_BUFFER_FLAG_REF : 0);
+    } else {
+        pic->f->width  = avctx->width;
+        pic->f->height = avctx->height;
+        pic->f->format = avctx->pix_fmt;
+        r = avcodec_default_get_buffer2(avctx, pic->f, 0);
+    }
+
+    if (r < 0 || !pic->f->buf[0]) {
+        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed (%d %p)\n",
+               r, pic->f->data[0]);
+        return -1;
+    }
+
+    if (edges_needed) {
+        int i;
+        for (i = 0; pic->f->data[i]; i++) {
+            int offset = (EDGE_WIDTH >> (i ? chroma_y_shift : 0)) *
+                         pic->f->linesize[i] +
+                         (EDGE_WIDTH >> (i ? chroma_x_shift : 0));
+            pic->f->data[i] += offset;
+        }
+        pic->f->width  = avctx->width;
+        pic->f->height = avctx->height;
+    }
+
+    if (avctx->hwaccel) {
+        assert(!pic->hwaccel_picture_private);
+        if (avctx->hwaccel->frame_priv_data_size) {
+            pic->hwaccel_priv_buf = av_buffer_allocz(avctx->hwaccel->frame_priv_data_size);
+            if (!pic->hwaccel_priv_buf) {
+                av_log(avctx, AV_LOG_ERROR, "alloc_frame_buffer() failed (hwaccel private data allocation)\n");
+                return -1;
+            }
+            pic->hwaccel_picture_private = pic->hwaccel_priv_buf->data;
+        }
+    }
+
+    if (linesize && (linesize   != pic->f->linesize[0] ||
+                     uvlinesize != pic->f->linesize[1])) {
+        av_log(avctx, AV_LOG_ERROR,
+               "get_buffer() failed (stride changed)\n");
+        ff_mpeg_unref_picture(avctx, pic);
+        return -1;
+    }
+
+    if (pic->f->linesize[1] != pic->f->linesize[2]) {
+        av_log(avctx, AV_LOG_ERROR,
+               "get_buffer() failed (uv stride mismatch)\n");
+        ff_mpeg_unref_picture(avctx, pic);
+        return -1;
+    }
+
+    if (!sc->edge_emu_buffer &&
+        (ret = ff_mpeg_framesize_alloc(avctx, me, sc,
+                                       pic->f->linesize[0])) < 0) {
+        av_log(avctx, AV_LOG_ERROR,
+               "get_buffer() failed to allocate context scratch buffers.\n");
+        ff_mpeg_unref_picture(avctx, pic);
+        return ret;
+    }
+
+    return 0;
+}
+
+static int alloc_picture_tables(Picture *pic, int encoding, int out_format,
+                                int mb_stride, int mb_height, int b8_stride)
+{
+    const int big_mb_num    = mb_stride * (mb_height + 1) + 1;
+    const int mb_array_size = mb_stride * mb_height;
+    const int b8_array_size = b8_stride * mb_height * 2;
+    int i;
+
+
+    pic->mbskip_table_buf = av_buffer_allocz(mb_array_size + 2);
+    pic->qscale_table_buf = av_buffer_allocz(big_mb_num + mb_stride);
+    pic->mb_type_buf      = av_buffer_allocz((big_mb_num + mb_stride) *
+                                             sizeof(uint32_t));
+    if (!pic->mbskip_table_buf || !pic->qscale_table_buf || !pic->mb_type_buf)
+        return AVERROR(ENOMEM);
+
+    if (encoding) {
+        pic->mb_var_buf    = av_buffer_allocz(mb_array_size * sizeof(int16_t));
+        pic->mc_mb_var_buf = av_buffer_allocz(mb_array_size * sizeof(int16_t));
+        pic->mb_mean_buf   = av_buffer_allocz(mb_array_size);
+        if (!pic->mb_var_buf || !pic->mc_mb_var_buf || !pic->mb_mean_buf)
+            return AVERROR(ENOMEM);
+    }
+
+    if (out_format == FMT_H263 || encoding) {
+        int mv_size        = 2 * (b8_array_size + 4) * sizeof(int16_t);
+        int ref_index_size = 4 * mb_array_size;
+
+        for (i = 0; mv_size && i < 2; i++) {
+            pic->motion_val_buf[i] = av_buffer_allocz(mv_size);
+            pic->ref_index_buf[i]  = av_buffer_allocz(ref_index_size);
+            if (!pic->motion_val_buf[i] || !pic->ref_index_buf[i])
+                return AVERROR(ENOMEM);
+        }
+    }
+
+    return 0;
+}
+
+/**
+ * Allocate a Picture.
+ * The pixels are allocated/set by calling get_buffer() if shared = 0
+ */
+int ff_alloc_picture(AVCodecContext *avctx, Picture *pic, MotionEstContext *me,
+                     ScratchpadContext *sc, int shared, int encoding,
+                     int chroma_x_shift, int chroma_y_shift, int out_format,
+                     int mb_stride, int mb_height, int b8_stride,
+                     ptrdiff_t *linesize, ptrdiff_t *uvlinesize)
+{
+    int i, ret;
+
+    if (shared) {
+        assert(pic->f->data[0]);
+        pic->shared = 1;
+    } else {
+        assert(!pic->f->buf[0]);
+        if (alloc_frame_buffer(avctx, pic, me, sc,
+                               chroma_x_shift, chroma_y_shift,
+                               *linesize, *uvlinesize) < 0)
+            return -1;
+
+        *linesize   = pic->f->linesize[0];
+        *uvlinesize = pic->f->linesize[1];
+    }
+
+    if (!pic->qscale_table_buf)
+        ret = alloc_picture_tables(pic, encoding, out_format,
+                                   mb_stride, mb_height, b8_stride);
+    else
+        ret = make_tables_writable(pic);
+    if (ret < 0)
+        goto fail;
+
+    if (encoding) {
+        pic->mb_var    = (uint16_t*)pic->mb_var_buf->data;
+        pic->mc_mb_var = (uint16_t*)pic->mc_mb_var_buf->data;
+        pic->mb_mean   = pic->mb_mean_buf->data;
+    }
+
+    pic->mbskip_table = pic->mbskip_table_buf->data;
+    pic->qscale_table = pic->qscale_table_buf->data + 2 * mb_stride + 1;
+    pic->mb_type      = (uint32_t*)pic->mb_type_buf->data + 2 * mb_stride + 1;
+
+    if (pic->motion_val_buf[0]) {
+        for (i = 0; i < 2; i++) {
+            pic->motion_val[i] = (int16_t (*)[2])pic->motion_val_buf[i]->data + 4;
+            pic->ref_index[i]  = pic->ref_index_buf[i]->data;
+        }
+    }
+
+    return 0;
+fail:
+    av_log(avctx, AV_LOG_ERROR, "Error allocating a picture.\n");
+    ff_mpeg_unref_picture(avctx, pic);
+    ff_free_picture_tables(pic);
+    return AVERROR(ENOMEM);
+}
+
+/**
+ * Deallocate a picture.
+ */
+void ff_mpeg_unref_picture(AVCodecContext *avctx, Picture *pic)
+{
+    pic->tf.f = pic->f;
+    /* WM Image / Screen codecs allocate internal buffers with different
+     * dimensions / colorspaces; ignore user-defined callbacks for these. */
+    if (avctx->codec_id != AV_CODEC_ID_WMV3IMAGE &&
+        avctx->codec_id != AV_CODEC_ID_VC1IMAGE  &&
+        avctx->codec_id != AV_CODEC_ID_MSS2)
+        ff_thread_release_buffer(avctx, &pic->tf);
+    else if (pic->f)
+        av_frame_unref(pic->f);
+
+    av_buffer_unref(&pic->hwaccel_priv_buf);
+
+    if (pic->needs_realloc)
+        ff_free_picture_tables(pic);
+}
+
+int ff_update_picture_tables(Picture *dst, Picture *src)
+{
+     int i;
+
+#define UPDATE_TABLE(table)                                                   \
+do {                                                                          \
+    if (src->table &&                                                         \
+        (!dst->table || dst->table->buffer != src->table->buffer)) {          \
+        av_buffer_unref(&dst->table);                                         \
+        dst->table = av_buffer_ref(src->table);                               \
+        if (!dst->table) {                                                    \
+            ff_free_picture_tables(dst);                                      \
+            return AVERROR(ENOMEM);                                           \
+        }                                                                     \
+    }                                                                         \
+} while (0)
+
+    UPDATE_TABLE(mb_var_buf);
+    UPDATE_TABLE(mc_mb_var_buf);
+    UPDATE_TABLE(mb_mean_buf);
+    UPDATE_TABLE(mbskip_table_buf);
+    UPDATE_TABLE(qscale_table_buf);
+    UPDATE_TABLE(mb_type_buf);
+    for (i = 0; i < 2; i++) {
+        UPDATE_TABLE(motion_val_buf[i]);
+        UPDATE_TABLE(ref_index_buf[i]);
+    }
+
+    dst->mb_var        = src->mb_var;
+    dst->mc_mb_var     = src->mc_mb_var;
+    dst->mb_mean       = src->mb_mean;
+    dst->mbskip_table  = src->mbskip_table;
+    dst->qscale_table  = src->qscale_table;
+    dst->mb_type       = src->mb_type;
+    for (i = 0; i < 2; i++) {
+        dst->motion_val[i] = src->motion_val[i];
+        dst->ref_index[i]  = src->ref_index[i];
+    }
+
+    return 0;
+}
+
+int ff_mpeg_ref_picture(AVCodecContext *avctx, Picture *dst, Picture *src)
+{
+    int ret;
+
+    av_assert0(!dst->f->buf[0]);
+    av_assert0(src->f->buf[0]);
+
+    src->tf.f = src->f;
+    dst->tf.f = dst->f;
+    ret = ff_thread_ref_frame(&dst->tf, &src->tf);
+    if (ret < 0)
+        goto fail;
+
+    ret = ff_update_picture_tables(dst, src);
+    if (ret < 0)
+        goto fail;
+
+    if (src->hwaccel_picture_private) {
+        dst->hwaccel_priv_buf = av_buffer_ref(src->hwaccel_priv_buf);
+        if (!dst->hwaccel_priv_buf)
+            goto fail;
+        dst->hwaccel_picture_private = dst->hwaccel_priv_buf->data;
+    }
+
+    dst->field_picture           = src->field_picture;
+    dst->mb_var_sum              = src->mb_var_sum;
+    dst->mc_mb_var_sum           = src->mc_mb_var_sum;
+    dst->b_frame_score           = src->b_frame_score;
+    dst->needs_realloc           = src->needs_realloc;
+    dst->reference               = src->reference;
+    dst->shared                  = src->shared;
+
+    return 0;
+fail:
+    ff_mpeg_unref_picture(avctx, dst);
+    return ret;
+}
+
+static inline int pic_is_unused(Picture *pic)
+{
+    if (!pic->f->buf[0])
+        return 1;
+    if (pic->needs_realloc && !(pic->reference & DELAYED_PIC_REF))
+        return 1;
+    return 0;
+}
+
+static int find_unused_picture(Picture *picture, int shared)
+{
+    int i;
+
+    if (shared) {
+        for (i = 0; i < MAX_PICTURE_COUNT; i++) {
+            if (!picture[i].f->buf[0])
+                return i;
+        }
+    } else {
+        for (i = 0; i < MAX_PICTURE_COUNT; i++) {
+            if (pic_is_unused(&picture[i]))
+                return i;
+        }
+    }
+
+    return AVERROR_INVALIDDATA;
+}
+
+int ff_find_unused_picture(AVCodecContext *avctx, Picture *picture, int shared)
+{
+    int ret = find_unused_picture(picture, shared);
+
+    if (ret >= 0 && ret < MAX_PICTURE_COUNT) {
+        if (picture[ret].needs_realloc) {
+            picture[ret].needs_realloc = 0;
+            ff_free_picture_tables(&picture[ret]);
+            ff_mpeg_unref_picture(avctx, &picture[ret]);
+        }
+    }
+    return ret;
+}
+
+void ff_free_picture_tables(Picture *pic)
+{
+    int i;
+
+    av_buffer_unref(&pic->mb_var_buf);
+    av_buffer_unref(&pic->mc_mb_var_buf);
+    av_buffer_unref(&pic->mb_mean_buf);
+    av_buffer_unref(&pic->mbskip_table_buf);
+    av_buffer_unref(&pic->qscale_table_buf);
+    av_buffer_unref(&pic->mb_type_buf);
+
+    for (i = 0; i < 2; i++) {
+        av_buffer_unref(&pic->motion_val_buf[i]);
+        av_buffer_unref(&pic->ref_index_buf[i]);
+    }
+}
diff --git a/libavcodec/mpegpicture.h b/libavcodec/mpegpicture.h
new file mode 100644
index 0000000..0588f02
--- /dev/null
+++ b/libavcodec/mpegpicture.h
@@ -0,0 +1,109 @@
+/*
+ * Mpeg video formats-related defines and utility functions
+ *
+ * This file is part of Libav.
+ *
+ * Libav 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.
+ *
+ * Libav 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 Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCODEC_MPEGPICTURE_H
+#define AVCODEC_MPEGPICTURE_H
+
+#include <stdint.h>
+
+#include "libavutil/frame.h"
+
+#include "avcodec.h"
+#include "motion_est.h"
+#include "thread.h"
+
+#define MAX_PICTURE_COUNT 32
+#define EDGE_WIDTH 16
+
+typedef struct ScratchpadContext {
+    uint8_t *edge_emu_buffer;     ///< temporary buffer for if MVs point to out-of-frame data
+    uint8_t *rd_scratchpad;       ///< scratchpad for rate distortion mb decision
+    uint8_t *obmc_scratchpad;
+    uint8_t *b_scratchpad;        ///< scratchpad used for writing into write only buffers
+} ScratchpadContext;
+
+/**
+ * Picture.
+ */
+typedef struct Picture {
+    struct AVFrame *f;
+    ThreadFrame tf;
+
+    AVBufferRef *qscale_table_buf;
+    int8_t *qscale_table;
+
+    AVBufferRef *motion_val_buf[2];
+    int16_t (*motion_val[2])[2];
+
+    AVBufferRef *mb_type_buf;
+    uint32_t *mb_type;          ///< types and macros are defined in mpegutils.h
+
+    AVBufferRef *mbskip_table_buf;
+    uint8_t *mbskip_table;
+
+    AVBufferRef *ref_index_buf[2];
+    int8_t *ref_index[2];
+
+    AVBufferRef *mb_var_buf;
+    uint16_t *mb_var;           ///< Table for MB variances
+
+    AVBufferRef *mc_mb_var_buf;
+    uint16_t *mc_mb_var;        ///< Table for motion compensated MB variances
+
+    AVBufferRef *mb_mean_buf;
+    uint8_t *mb_mean;           ///< Table for MB luminance
+
+    AVBufferRef *hwaccel_priv_buf;
+    void *hwaccel_picture_private; ///< Hardware accelerator private data
+
+    int field_picture;          ///< whether or not the picture was encoded in separate fields
+
+    int mb_var_sum;             ///< sum of MB variance for current frame
+    int mc_mb_var_sum;          ///< motion compensated MB variance for current frame
+
+    int b_frame_score;          /* */
+    int needs_realloc;          ///< Picture needs to be reallocated (eg due to a frame size change)
+
+    int reference;
+    int shared;
+} Picture;
+
+/**
+ * Allocate a Picture.
+ * The pixels are allocated/set by calling get_buffer() if shared = 0.
+ */
+int ff_alloc_picture(AVCodecContext *avctx, Picture *pic, MotionEstContext *me,
+                     ScratchpadContext *sc, int shared, int encoding,
+                     int chroma_x_shift, int chroma_y_shift, int out_format,
+                     int mb_stride, int mb_height, int b8_stride,
+                     ptrdiff_t *linesize, ptrdiff_t *uvlinesize);
+
+int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
+                            ScratchpadContext *sc, int linesize);
+
+int ff_mpeg_ref_picture(AVCodecContext *avctx, Picture *dst, Picture *src);
+void ff_mpeg_unref_picture(AVCodecContext *avctx, Picture *picture);
+
+void ff_free_picture_tables(Picture *pic);
+int ff_update_picture_tables(Picture *dst, Picture *src);
+
+int ff_find_unused_picture(AVCodecContext *avctx, Picture *picture, int shared);
+
+#endif /* AVCODEC_MPEGPICTURE_H */
diff --git a/libavcodec/mpegvideo.c b/libavcodec/mpegvideo.c
index 2b938a6..86eab07 100644
--- a/libavcodec/mpegvideo.c
+++ b/libavcodec/mpegvideo.c
@@ -343,199 +343,6 @@ av_cold void ff_mpv_idct_init(MpegEncContext *s)
     ff_init_scantable(s->idsp.idct_permutation, &s->intra_v_scantable, ff_alternate_vertical_scan);
 }
 
-int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
-                            ScratchpadContext *sc, int linesize)
-{
-    int alloc_size = FFALIGN(FFABS(linesize) + 32, 32);
-
-    // edge emu needs blocksize + filter length - 1
-    // (= 17x17 for  halfpel / 21x21 for  h264)
-    // VC1 computes luma and chroma simultaneously and needs 19X19 + 9x9
-    // at uvlinesize. It supports only YUV420 so 24x24 is enough
-    // linesize * interlaced * MBsize
-    FF_ALLOCZ_OR_GOTO(avctx, sc->edge_emu_buffer, alloc_size * 2 * 24,
-                      fail);
-
-    FF_ALLOCZ_OR_GOTO(avctx, me->scratchpad, alloc_size * 2 * 16 * 3,
-                      fail)
-    me->temp            = me->scratchpad;
-    sc->rd_scratchpad   = me->scratchpad;
-    sc->b_scratchpad    = me->scratchpad;
-    sc->obmc_scratchpad = me->scratchpad + 16;
-
-    return 0;
-fail:
-    av_freep(&sc->edge_emu_buffer);
-    return AVERROR(ENOMEM);
-}
-
-/**
- * Allocate a frame buffer
- */
-static int alloc_frame_buffer(AVCodecContext *avctx, Picture *pic,
-                              MotionEstContext *me, ScratchpadContext *sc,
-                              int chroma_x_shift, int chroma_y_shift,
-                              int linesize, int uvlinesize)
-{
-    int edges_needed = av_codec_is_encoder(avctx->codec);
-    int r, ret;
-
-    pic->tf.f = pic->f;
-    if (avctx->codec_id != AV_CODEC_ID_WMV3IMAGE &&
-        avctx->codec_id != AV_CODEC_ID_VC1IMAGE  &&
-        avctx->codec_id != AV_CODEC_ID_MSS2) {
-        if (edges_needed) {
-            pic->f->width  = avctx->width  + 2 * EDGE_WIDTH;
-            pic->f->height = avctx->height + 2 * EDGE_WIDTH;
-        }
-
-        r = ff_thread_get_buffer(avctx, &pic->tf,
-                                 pic->reference ? AV_GET_BUFFER_FLAG_REF : 0);
-    } else {
-        pic->f->width  = avctx->width;
-        pic->f->height = avctx->height;
-        pic->f->format = avctx->pix_fmt;
-        r = avcodec_default_get_buffer2(avctx, pic->f, 0);
-    }
-
-    if (r < 0 || !pic->f->buf[0]) {
-        av_log(avctx, AV_LOG_ERROR, "get_buffer() failed (%d %p)\n",
-               r, pic->f->data[0]);
-        return -1;
-    }
-
-    if (edges_needed) {
-        int i;
-        for (i = 0; pic->f->data[i]; i++) {
-            int offset = (EDGE_WIDTH >> (i ? chroma_y_shift : 0)) *
-                         pic->f->linesize[i] +
-                         (EDGE_WIDTH >> (i ? chroma_x_shift : 0));
-            pic->f->data[i] += offset;
-        }
-        pic->f->width  = avctx->width;
-        pic->f->height = avctx->height;
-    }
-
-    if (avctx->hwaccel) {
-        assert(!pic->hwaccel_picture_private);
-        if (avctx->hwaccel->frame_priv_data_size) {
-            pic->hwaccel_priv_buf = av_buffer_allocz(avctx->hwaccel->frame_priv_data_size);
-            if (!pic->hwaccel_priv_buf) {
-                av_log(avctx, AV_LOG_ERROR, "alloc_frame_buffer() failed (hwaccel private data allocation)\n");
-                return -1;
-            }
-            pic->hwaccel_picture_private = pic->hwaccel_priv_buf->data;
-        }
-    }
-
-    if (linesize && (linesize   != pic->f->linesize[0] ||
-                     uvlinesize != pic->f->linesize[1])) {
-        av_log(avctx, AV_LOG_ERROR,
-               "get_buffer() failed (stride changed)\n");
-        ff_mpeg_unref_picture(avctx, pic);
-        return -1;
-    }
-
-    if (pic->f->linesize[1] != pic->f->linesize[2]) {
-        av_log(avctx, AV_LOG_ERROR,
-               "get_buffer() failed (uv stride mismatch)\n");
-        ff_mpeg_unref_picture(avctx, pic);
-        return -1;
-    }
-
-    if (!sc->edge_emu_buffer &&
-        (ret = ff_mpeg_framesize_alloc(avctx, me, sc,
-                                       pic->f->linesize[0])) < 0) {
-        av_log(avctx, AV_LOG_ERROR,
-               "get_buffer() failed to allocate context scratch buffers.\n");
-        ff_mpeg_unref_picture(avctx, pic);
-        return ret;
-    }
-
-    return 0;
-}
-
-void ff_free_picture_tables(Picture *pic)
-{
-    int i;
-
-    av_buffer_unref(&pic->mb_var_buf);
-    av_buffer_unref(&pic->mc_mb_var_buf);
-    av_buffer_unref(&pic->mb_mean_buf);
-    av_buffer_unref(&pic->mbskip_table_buf);
-    av_buffer_unref(&pic->qscale_table_buf);
-    av_buffer_unref(&pic->mb_type_buf);
-
-    for (i = 0; i < 2; i++) {
-        av_buffer_unref(&pic->motion_val_buf[i]);
-        av_buffer_unref(&pic->ref_index_buf[i]);
-    }
-}
-
-static int alloc_picture_tables(Picture *pic, int encoding, int out_format,
-                                int mb_stride, int mb_height, int b8_stride)
-{
-    const int big_mb_num    = mb_stride * (mb_height + 1) + 1;
-    const int mb_array_size = mb_stride * mb_height;
-    const int b8_array_size = b8_stride * mb_height * 2;
-    int i;
-
-
-    pic->mbskip_table_buf = av_buffer_allocz(mb_array_size + 2);
-    pic->qscale_table_buf = av_buffer_allocz(big_mb_num + mb_stride);
-    pic->mb_type_buf      = av_buffer_allocz((big_mb_num + mb_stride) *
-                                             sizeof(uint32_t));
-    if (!pic->mbskip_table_buf || !pic->qscale_table_buf || !pic->mb_type_buf)
-        return AVERROR(ENOMEM);
-
-    if (encoding) {
-        pic->mb_var_buf    = av_buffer_allocz(mb_array_size * sizeof(int16_t));
-        pic->mc_mb_var_buf = av_buffer_allocz(mb_array_size * sizeof(int16_t));
-        pic->mb_mean_buf   = av_buffer_allocz(mb_array_size);
-        if (!pic->mb_var_buf || !pic->mc_mb_var_buf || !pic->mb_mean_buf)
-            return AVERROR(ENOMEM);
-    }
-
-    if (out_format == FMT_H263 || encoding) {
-        int mv_size        = 2 * (b8_array_size + 4) * sizeof(int16_t);
-        int ref_index_size = 4 * mb_array_size;
-
-        for (i = 0; mv_size && i < 2; i++) {
-            pic->motion_val_buf[i] = av_buffer_allocz(mv_size);
-            pic->ref_index_buf[i]  = av_buffer_allocz(ref_index_size);
-            if (!pic->motion_val_buf[i] || !pic->ref_index_buf[i])
-                return AVERROR(ENOMEM);
-        }
-    }
-
-    return 0;
-}
-
-static int make_tables_writable(Picture *pic)
-{
-    int ret, i;
-#define MAKE_WRITABLE(table) \
-do {\
-    if (pic->table &&\
-       (ret = av_buffer_make_writable(&pic->table)) < 0)\
-    return ret;\
-} while (0)
-
-    MAKE_WRITABLE(mb_var_buf);
-    MAKE_WRITABLE(mc_mb_var_buf);
-    MAKE_WRITABLE(mb_mean_buf);
-    MAKE_WRITABLE(mbskip_table_buf);
-    MAKE_WRITABLE(qscale_table_buf);
-    MAKE_WRITABLE(mb_type_buf);
-
-    for (i = 0; i < 2; i++) {
-        MAKE_WRITABLE(motion_val_buf[i]);
-        MAKE_WRITABLE(ref_index_buf[i]);
-    }
-
-    return 0;
-}
-
 static int alloc_picture(MpegEncContext *s, Picture *pic, int shared)
 {
     return ff_alloc_picture(s->avctx, pic, &s->me, &s->sc, shared, 0,
@@ -544,166 +351,6 @@ static int alloc_picture(MpegEncContext *s, Picture *pic, int shared)
                             &s->linesize, &s->uvlinesize);
 }
 
-/**
- * Allocate a Picture.
- * The pixels are allocated/set by calling get_buffer() if shared = 0
- */
-int ff_alloc_picture(AVCodecContext *avctx, Picture *pic, MotionEstContext *me,
-                     ScratchpadContext *sc, int shared, int encoding,
-                     int chroma_x_shift, int chroma_y_shift, int out_format,
-                     int mb_stride, int mb_height, int b8_stride,
-                     ptrdiff_t *linesize, ptrdiff_t *uvlinesize)
-{
-    int i, ret;
-
-    if (shared) {
-        assert(pic->f->data[0]);
-        pic->shared = 1;
-    } else {
-        assert(!pic->f->buf[0]);
-        if (alloc_frame_buffer(avctx, pic, me, sc,
-                               chroma_x_shift, chroma_y_shift,
-                               *linesize, *uvlinesize) < 0)
-            return -1;
-
-        *linesize   = pic->f->linesize[0];
-        *uvlinesize = pic->f->linesize[1];
-    }
-
-    if (!pic->qscale_table_buf)
-        ret = alloc_picture_tables(pic, encoding, out_format,
-                                   mb_stride, mb_height, b8_stride);
-    else
-        ret = make_tables_writable(pic);
-    if (ret < 0)
-        goto fail;
-
-    if (encoding) {
-        pic->mb_var    = (uint16_t*)pic->mb_var_buf->data;
-        pic->mc_mb_var = (uint16_t*)pic->mc_mb_var_buf->data;
-        pic->mb_mean   = pic->mb_mean_buf->data;
-    }
-
-    pic->mbskip_table = pic->mbskip_table_buf->data;
-    pic->qscale_table = pic->qscale_table_buf->data + 2 * mb_stride + 1;
-    pic->mb_type      = (uint32_t*)pic->mb_type_buf->data + 2 * mb_stride + 1;
-
-    if (pic->motion_val_buf[0]) {
-        for (i = 0; i < 2; i++) {
-            pic->motion_val[i] = (int16_t (*)[2])pic->motion_val_buf[i]->data + 4;
-            pic->ref_index[i]  = pic->ref_index_buf[i]->data;
-        }
-    }
-
-    return 0;
-fail:
-    av_log(avctx, AV_LOG_ERROR, "Error allocating a picture.\n");
-    ff_mpeg_unref_picture(avctx, pic);
-    ff_free_picture_tables(pic);
-    return AVERROR(ENOMEM);
-}
-
-/**
- * Deallocate a picture.
- */
-void ff_mpeg_unref_picture(AVCodecContext *avctx, Picture *pic)
-{
-    pic->tf.f = pic->f;
-    /* WM Image / Screen codecs allocate internal buffers with different
-     * dimensions / colorspaces; ignore user-defined callbacks for these. */
-    if (avctx->codec->id != AV_CODEC_ID_WMV3IMAGE &&
-        avctx->codec->id != AV_CODEC_ID_VC1IMAGE  &&
-        avctx->codec->id != AV_CODEC_ID_MSS2)
-        ff_thread_release_buffer(avctx, &pic->tf);
-    else if (pic->f)
-        av_frame_unref(pic->f);
-
-    av_buffer_unref(&pic->hwaccel_priv_buf);
-
-    if (pic->needs_realloc)
-        ff_free_picture_tables(pic);
-}
-
-static int update_picture_tables(Picture *dst, Picture *src)
-{
-     int i;
-
-#define UPDATE_TABLE(table)\
-do {\
-    if (src->table &&\
-        (!dst->table || dst->table->buffer != src->table->buffer)) {\
-        av_buffer_unref(&dst->table);\
-        dst->table = av_buffer_ref(src->table);\
-        if (!dst->table) {\
-            ff_free_picture_tables(dst);\
-            return AVERROR(ENOMEM);\
-        }\
-    }\
-} while (0)
-
-    UPDATE_TABLE(mb_var_buf);
-    UPDATE_TABLE(mc_mb_var_buf);
-    UPDATE_TABLE(mb_mean_buf);
-    UPDATE_TABLE(mbskip_table_buf);
-    UPDATE_TABLE(qscale_table_buf);
-    UPDATE_TABLE(mb_type_buf);
-    for (i = 0; i < 2; i++) {
-        UPDATE_TABLE(motion_val_buf[i]);
-        UPDATE_TABLE(ref_index_buf[i]);
-    }
-
-    dst->mb_var        = src->mb_var;
-    dst->mc_mb_var     = src->mc_mb_var;
-    dst->mb_mean       = src->mb_mean;
-    dst->mbskip_table  = src->mbskip_table;
-    dst->qscale_table  = src->qscale_table;
-    dst->mb_type       = src->mb_type;
-    for (i = 0; i < 2; i++) {
-        dst->motion_val[i] = src->motion_val[i];
-        dst->ref_index[i]  = src->ref_index[i];
-    }
-
-    return 0;
-}
-
-int ff_mpeg_ref_picture(AVCodecContext *avctx, Picture *dst, Picture *src)
-{
-    int ret;
-
-    av_assert0(!dst->f->buf[0]);
-    av_assert0(src->f->buf[0]);
-
-    src->tf.f = src->f;
-    dst->tf.f = dst->f;
-    ret = ff_thread_ref_frame(&dst->tf, &src->tf);
-    if (ret < 0)
-        goto fail;
-
-    ret = update_picture_tables(dst, src);
-    if (ret < 0)
-        goto fail;
-
-    if (src->hwaccel_picture_private) {
-        dst->hwaccel_priv_buf = av_buffer_ref(src->hwaccel_priv_buf);
-        if (!dst->hwaccel_priv_buf)
-            goto fail;
-        dst->hwaccel_picture_private = dst->hwaccel_priv_buf->data;
-    }
-
-    dst->field_picture           = src->field_picture;
-    dst->mb_var_sum              = src->mb_var_sum;
-    dst->mc_mb_var_sum           = src->mc_mb_var_sum;
-    dst->b_frame_score           = src->b_frame_score;
-    dst->needs_realloc           = src->needs_realloc;
-    dst->reference               = src->reference;
-    dst->shared                  = src->shared;
-
-    return 0;
-fail:
-    ff_mpeg_unref_picture(avctx, dst);
-    return ret;
-}
-
 static int init_duplicate_context(MpegEncContext *s)
 {
     int y_size = s->b8_stride * (2 * s->mb_height + 1);
@@ -888,7 +535,7 @@ do {\
     if (s1->pic.f->buf[0])\
         ret = ff_mpeg_ref_picture(s->avctx, &s->pic, &s1->pic);\
     else\
-        ret = update_picture_tables(&s->pic, &s1->pic);\
+        ret = ff_update_picture_tables(&s->pic, &s1->pic);\
     if (ret < 0)\
         return ret;\
 } while (0)
@@ -1473,48 +1120,6 @@ static void release_unused_pictures(AVCodecContext *avctx, Picture *picture)
     }
 }
 
-static inline int pic_is_unused(Picture *pic)
-{
-    if (!pic->f->buf[0])
-        return 1;
-    if (pic->needs_realloc && !(pic->reference & DELAYED_PIC_REF))
-        return 1;
-    return 0;
-}
-
-static int find_unused_picture(Picture *picture, int shared)
-{
-    int i;
-
-    if (shared) {
-        for (i = 0; i < MAX_PICTURE_COUNT; i++) {
-            if (!picture[i].f->buf[0])
-                return i;
-        }
-    } else {
-        for (i = 0; i < MAX_PICTURE_COUNT; i++) {
-            if (pic_is_unused(&picture[i]))
-                return i;
-        }
-    }
-
-    return AVERROR_INVALIDDATA;
-}
-
-int ff_find_unused_picture(AVCodecContext *avctx, Picture *picture, int shared)
-{
-    int ret = find_unused_picture(picture, shared);
-
-    if (ret >= 0 && ret < MAX_PICTURE_COUNT) {
-        if (picture[ret].needs_realloc) {
-            picture[ret].needs_realloc = 0;
-            ff_free_picture_tables(&picture[ret]);
-            ff_mpeg_unref_picture(avctx, &picture[ret]);
-        }
-    }
-    return ret;
-}
-
 /**
  * generic function called after decoding
  * the header and before a frame is decoded.
diff --git a/libavcodec/mpegvideo.h b/libavcodec/mpegvideo.h
index d5e14f7..b2b2f6d 100644
--- a/libavcodec/mpegvideo.h
+++ b/libavcodec/mpegvideo.h
@@ -40,6 +40,7 @@
 #include "idctdsp.h"
 #include "me_cmp.h"
 #include "motion_est.h"
+#include "mpegpicture.h"
 #include "mpegvideodsp.h"
 #include "mpegvideoencdsp.h"
 #include "pixblockdsp.h"
@@ -60,8 +61,6 @@
 
 #define MAX_THREADS 16
 
-#define MAX_PICTURE_COUNT 32
-
 #define MAX_B_FRAMES 16
 
 #define ME_MAP_SIZE 64
@@ -70,8 +69,6 @@
 
 #define INPLACE_OFFSET 16
 
-#define EDGE_WIDTH 16
-
 /* Start codes. */
 #define SEQ_END_CODE            0x000001b7
 #define SEQ_START_CODE          0x000001b3
@@ -83,62 +80,6 @@
 #define USER_START_CODE         0x000001b2
 
 /**
- * Picture.
- */
-typedef struct Picture{
-    struct AVFrame *f;
-    ThreadFrame tf;
-
-    AVBufferRef *qscale_table_buf;
-    int8_t *qscale_table;
-
-    AVBufferRef *motion_val_buf[2];
-    int16_t (*motion_val[2])[2];
-
-    AVBufferRef *mb_type_buf;
-    uint32_t *mb_type;          ///< types and macros are defined in mpegutils.h
-
-    AVBufferRef *mbskip_table_buf;
-    uint8_t *mbskip_table;
-
-    AVBufferRef *ref_index_buf[2];
-    int8_t *ref_index[2];
-
-    AVBufferRef *mb_var_buf;
-    uint16_t *mb_var;           ///< Table for MB variances
-
-    AVBufferRef *mc_mb_var_buf;
-    uint16_t *mc_mb_var;        ///< Table for motion compensated MB variances
-
-    AVBufferRef *mb_mean_buf;
-    uint8_t *mb_mean;           ///< Table for MB luminance
-
-    AVBufferRef *hwaccel_priv_buf;
-    /**
-     * hardware accelerator private data
-     */
-    void *hwaccel_picture_private;
-
-    int field_picture;          ///< whether or not the picture was encoded in separate fields
-
-    int mb_var_sum;             ///< sum of MB variance for current frame
-    int mc_mb_var_sum;          ///< motion compensated MB variance for current frame
-
-    int b_frame_score;          /* */
-    int needs_realloc;          ///< Picture needs to be reallocated (eg due to a frame size change)
-
-    int reference;
-    int shared;
-} Picture;
-
-typedef struct ScratchpadContext {
-    uint8_t *edge_emu_buffer;     ///< temporary buffer for if MVs point to out-of-frame data
-    uint8_t *rd_scratchpad;       ///< scratchpad for rate distortion mb decision
-    uint8_t *obmc_scratchpad;
-    uint8_t *b_scratchpad;        ///< scratchpad used for writing into write only buffers
-} ScratchpadContext;
-
-/**
  * MpegEncContext.
  */
 typedef struct MpegEncContext {
@@ -679,7 +620,6 @@ void ff_mpeg_flush(AVCodecContext *avctx);
 void ff_print_debug_info(MpegEncContext *s, Picture *p);
 void ff_write_quant_matrix(PutBitContext *pb, uint16_t *matrix);
 
-int ff_find_unused_picture(AVCodecContext *avctx, Picture *picture, int shared);
 int ff_update_duplicate_context(MpegEncContext *dst, MpegEncContext *src);
 int ff_mpeg_update_thread_context(AVCodecContext *dst, const AVCodecContext *src);
 void ff_set_qscale(MpegEncContext * s, int qscale);
@@ -699,18 +639,6 @@ void ff_mpv_motion(MpegEncContext *s,
                    qpel_mc_func (*qpix_op)[16]);
 
 /**
- * Allocate a Picture.
- * The pixels are allocated/set by calling get_buffer() if shared = 0.
- */
-int ff_alloc_picture(AVCodecContext *avctx, Picture *pic, MotionEstContext *me,
-                     ScratchpadContext *sc, int shared, int encoding,
-                     int chroma_x_shift, int chroma_y_shift, int out_format,
-                     int mb_stride, int mb_height, int b8_stride,
-                     ptrdiff_t *linesize, ptrdiff_t *uvlinesize);
-
-int ff_mpeg_framesize_alloc(AVCodecContext *avctx, MotionEstContext *me,
-                            ScratchpadContext *sc, int linesize);
-/**
  * permute block according to permuatation.
  * @param last last non zero element in scantable order
  */
@@ -744,8 +672,4 @@ int ff_rv10_encode_picture_header(MpegEncContext *s, int picture_number);
 int ff_rv_decode_dc(MpegEncContext *s, int n);
 void ff_rv20_encode_picture_header(MpegEncContext *s, int picture_number);
 
-int ff_mpeg_ref_picture(AVCodecContext *avctx, Picture *dst, Picture *src);
-void ff_mpeg_unref_picture(AVCodecContext *avctx, Picture *picture);
-void ff_free_picture_tables(Picture *pic);
-
 #endif /* AVCODEC_MPEGVIDEO_H */